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U.S. Declares War on Mexico

U.S. Declares War on Mexico

On May 13, 1846, the U.S. Congress overwhelmingly votes in favor of President James K. Polk’s request to declare war on Mexico in a dispute over Texas.

Under the threat of war, the United States had refrained from annexing Texas after the latter won independence from Mexico in 1836. But in 1844, President John Tyler restarted negotiations with the Republic of Texas, culminating with a Treaty of Annexation. The treaty was defeated by a wide margin in the Senate because it would upset the slave state/free state balance between North and South and risked war with Mexico, which had broken off relations with the United States. But shortly before leaving office and with the support of President-elect Polk, Tyler managed to get the joint resolution passed on March 1, 1845. Texas was admitted to the Union on December 29.

While Mexico didn’t follow through with its threat to declare war, relations between the two nations remained tense over border disputes, and in July 1845, President Polk ordered troops into disputed lands that lay between the Neuces and Rio Grande rivers. In November, Polk sent the diplomat John Slidell to Mexico to seek boundary adjustments in return for the U.S. government’s settlement of the claims of U.S. citizens against Mexico and also to make an offer to purchase California and New Mexico. After the mission failed, the U.S. army under Gen. Zachary Taylor advanced to the mouth of the Rio Grande, the river that the state of Texas claimed as its southern boundary.

Mexico, claiming that the boundary was the Nueces River to the northeast of the Rio Grande, considered the advance of Taylor’s army an act of aggression and in April 1846 sent troops across the Rio Grande. Polk, in turn, declared the Mexican advance to be an invasion of U.S. soil, and on May 11, 1846, asked Congress to declare war on Mexico, which it did two days later.

After nearly two years of fighting, peace was established by the Treaty of Guadalupe Hidalgo, signed on February 2, 1848. The Rio Grande was made the southern boundary of Texas, and California and New Mexico were ceded to the United States. In return, the United States paid Mexico the sum of $15 million and agreed to settle all claims of U.S. citizens against Mexico.

READ MORE: 10 Things You May Not Know About the Mexican-American War

United States declaration of war upon Mexico

On May 13, 1846 the United States Congress passed An Act providing for the Prosecution of the existing War between the United States and the Republic of Mexico, thereby declaring war against Mexico. The declaration resulted in the Mexican–American War (1846–48). The act laid out regulations for the size and organization of the militia to participate in the war, how they were to be recruited, and the amount of money appropriated for the war—10 million dollars. The act was amended on June 18, 1846 (9 Stat. 17) to clarify and expand the organizational structure provided for by the original law. [ citation needed ]

United States declaration of war upon Mexico
Long title"An Act providing for the Prosecution of the existing War between the United States and the Republic of Mexico."
Enacted bythe 29th United States Congress
EffectiveMay 13, 1846
Statutes at Large 9 Stat. 9
Major amendments
Amended by subsequent legislation, 9 Stat. 17

Whereas, by the act of the Republic of Mexico, a state of war exists between that Government and the United States:

Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That, for the purpose of enabling the government of the United States to prosecute said war to a speedy and successful termination, the President be, and he is hereby, authorized to employ the militia, naval, and military forces of the United States, and to call for and accept the services of any number of volunteers, not exceeding fifty thousand, who may offer their services, either as cavalry, artillery, infantry, or riflemen, to serve twelve months after they shall have arrived at the place of rendezvous, or to the end of the war, unless sooner discharged, according to the time for which they shall have been mustered into service and that the sum of ten millions of dollars, out of any moneys in the treasury, or to come into the treasury, not otherwise appropriated, be, and the same is hereby, appropriated for the purpose of carrying the provisions of this act into effect.

SEC. 2. And be it further enacted, That the militia, when called into the service of the United States by virtue of this act, or any other act, may, if in the opinion of the President of the United States the public interest requires it, be compelled to serve for a term not exceeding six months after their arrival at the place of rendezvous, in any one year, unless sooner discharged.

SEC. 3. And be it further enacted, That the said volunteers shall furnish their own clothes, and if cavalry, their own horses and horse equipments and when mustered into service shall be armed at the expense of the United States.

SEC. 4. And be it further enacted, That said volunteers shall, when called into actual service, and while remaining therein, be subject to the rules and articles of war, and shall be, in all respects except as to clothing and pay, placed on the same footing with similar corps of the United States army and in lieu of clothing every non-commissioned officer and private in any company, who may thus offer himself, shall be entitled, when called into actual service, to receive in money a sum equal to the cost of clothing of a non-commissioned officer or private (as the case may be) in the regular troops of the United States.

SEC 5. And be it further enacted, That the said volunteers so offering their services shall be accepted by the President in companies, battalions, squadrons, and regiments, whose officers shall be appointed in the manner prescribed by law in the several States and Territories to which such companies, battalions, squadrons, and regiments, shall respectively belong.

SEC. 6. And be it further enacted, That the President of the United States be, and he is hereby, authorized to organize companies so tendering their service into battalions or squadrons, battalions and squadrons into regiments, regiments into brigades, and brigades into divisions, as soon as the number of volunteers shall render such organization, in his judgment, expedient and the President shall, if necessary, apportion the staff, field, and general officers among the respective States and Territories from which the volunteers shall tender their services as he may deem proper.

SEC 7. And be it further enacted, That the volunteers who may be received into the service of the United States by virtue of the provisions of this act, and who shall be wounded or otherwise disabled in the service, shall be entitled to all the benefit which may be conferred on persons wounded in the service of the United States.

SEC 8. And be it further enacted, That the President of the United States be, and he is hereby, authorized forthwith to complete all the public armed vessels now authorized by law, and to purchase or charter, arm, equip, and man, such merchant vessels and steam boats as, upon examination, may be found fit, or easily converted into armed vessels fit for the public service, and in such number as he may deem necessary for the protection of the seaboard, lake coast, and the general defense of the country.

SEC. 9. And be it further enacted, That whenever the militia or volunteers are called and received into the service of the United States, under the provisions of this act, they shall have the organization of the army of the United States, and shall have the same pay and allowances and all mounted privates, non-commissioned officers, musicians, and artificers, shall be allowed 40 cents per day for the use and risk of their horses, except of horses actually killed in action and if any mounted volunteer, private, non-commissioned officer, musician, or artificer, shall not keep himself provided with a serviceable horse, the said volunteer shall serve on foot.

The United States Declares War on Mexico

On April 26, 1846, following a tense stand-off between U.S. and Mexican troops on the banks of the Rio Grande (which the U.S. now claimed as its border with Mexico, having annexed the state of Texas), a small patrol of sixty-three U.S. soldiers was attacked by Mexican forces, with eleven Americans killed. In response, U.S. General Zachary Taylor engaged the Mexican army in battles at Palo Alto and Resaca de la Palma, and informed President Polk that hostilities between the two nations had begun. On May 11th, Polk sent this declaration of war to Congress, claiming that Mexico had started the war by "shedding American blood upon American soil."

To the Senate and the House of Representatives:

The existing state of the relations between the United States and Mexico renders it proper that I should bring the subject to the consideration of Congress. In my message at the commencement of your present session, the state of these relations, the causes which led to the suspension of diplomatic intercourse between the two countries in March, 1845, and the long-continued and unredressed wrongs and injuries committed by the Mexican Government on citizens of the United States in their persons and property were briefly set forth.

The strong desire to establish peace with Mexico on liberal and honorable terms, and the readiness of this Government to regulate and adjust our boundary and other causes of difference with that power on such fair and equitable principles as would lead to permanent relations of the most friendly nature, induced me in September last to seek the reopening of diplomatic relations between the two countries. Every measure adopted on our part had for its object the furtherance of these desired results. In communicating to Congress a succinct statement of the injuries which we had suffered from Mexico, and which have been accumulating during a period of more than twenty years, every expression that could tend to inflame the people of Mexico or defeat or delay a pacific result was carefully avoided. An envoy of the United States repaired to Mexico with full powers to adjust every existing difference. But through present on Mexican soil by agreement between the two Governments, invested with full powers, and bearing evidence of the most friendly dispositions, his mission has been unavailing. The Mexican Government not only refused to receive him or listen to his propositions, but after a long-continued series of menaces have at last invaded our territory and shed the blood of our fellow-citizens on our own soil.

The grievous wrongs perpetrated by Mexico upon our citizens throughout a period of years remain unredressed, and solemn treaties pledging her public faith for this redress have been disregarded. A government either unable or unwilling to enforce the execution of such treaties fails to perform one of its plainest duties.

We have tried every effort at reconciliation. The cup of forbearance had been exhausted even before the recent information from the frontier of Del Norte. But now, after reiterated menaces, Mexico has passed the boundary of the United States, has invaded our territory and shed American blood upon American soil. She has proclaimed that hostilities have commenced, and that the two nations are now at war.

As war exists, and, notwithstanding all our efforts to avoid it, exists by the act of Mexico herself, we are called upon by every consideration of duty and patriotism to vindicate with decision the honor, the rights, and interests of our country.

In further vindication of our rights and defense of our territory, I invoke the prompt action of Congress to recognize the existence of the war, and to place at the disposition of the Executive the means of prosecuting the war with vigor, and thus hastening the restoration of peace.

In making these recommendations I deem it proper to declare that it is my anxious desire not only to terminate hostilities speedily, but to bring all matters in dispute between this Government and Mexico to an early and amicable adjustment and in this view I shall be prepared to renew negotiations whenever Mexico shall be ready to receive propositions or to propositions of her own.

I transmit herewith a copy of the correspondence between our envoy to Mexico and the Mexican minister for foreign affairs, and so much of the correspondence between that envoy and the Secretary of State and between the Secretary of War and the general in command on the Del Norte as is necessary to a full understanding of the subject.

Spot Resolutions and Civil Disobedience: American opposition to the war

Congress overwhelmingly approved a declaration of war on May 13, but the United States entered the war divided. Democrats, especially those in the Southwest, strongly favoured the conflict. Most Whigs viewed Polk’s motives as conscienceless land grabbing. Indeed, from the outset, Whigs in both the Senate and the House challenged the veracity of Polk’s assertion that the initial conflict between U.S. and Mexican forces had taken place in U.S. territory. Further, legislators were at odds over whether Polk had the right to unilaterally declare that a state of war existed. Principally at issue was where the encounter had actually taken place and the willingness of Americans to acknowledge the Mexican contention that the Nueces River formed the border between the two countries. Active Whig opposition not only to the legitimacy of Polk’s claim but also to the war itself continued well into the conflict. In December 1846 Polk accused his Whig doubters of treason. In January 1847 the by-then Whig-controlled House voted 85 to 81 to censure Polk for having “unnecessarily and unconstitutionally” initiated war with Mexico.

Among the most-aggressive challenges to the legitimacy of Polk’s casus belli was that offered by future president Abraham Lincoln, then a first-term member of the House of Representatives from Illinois. In December 1847 Lincoln introduced eight “ Spot Resolutions,” which placed the analysis of Polk’s claim in a carefully delineated historical context that sought to

obtain a full knowledge of all the facts which go to establish whether the particular spot of soil on which the blood of our citizens was so shed was, or was not, our own soil at that time.

Ultimately, the House did not act on Lincoln’s resolutions, and Polk remained steadfast in his claim that the conflict was a just war.

Abolitionists saw the war as an attempt by the slave states to extend slavery and enhance their power with the creation of additional slave states out of the soon-to-be-acquired Mexican lands. One abolitionist who agreed with that interpretation was author Henry David Thoreau, who was incarcerated in July 1846 when he refused to pay six years’ worth of back poll taxes because he felt the U.S. government’s prosecution of the war with Mexico was immoral. Although he spent only a single night in jail (his aunt, against his wishes, paid the taxes, thus securing his release), Thoreau documented his opposition to the government’s actions in his famous book-length essay Civil Disobedience (1849), insisting that if an injustice of government is

of such a nature that it requires you to be the agent of injustice to another, then, I say, break the law. Let your life be a counter friction to stop the machine.

The U.S. declares war on Mexico

Part 3 of our series on interesting facts and background to the Mexican War addresses the U.S. declaration of war and the factors leading up to it.

You will recall from part 2 that the U.S. saw two distinct threats to its ability to gain control of the Pacific Coast: Britain, which owned land from the southern border of today’s Alaska to the current southern border of British Columbia, Canada, and which had designs on the disputed territory just south (today’s States of Washington and Oregon) and Mexico, which owned Upper California (today’s State of California). Britain was taken out of the picture by the 1846 Oregon Treaty, which removed British claims to the disputed territory. Now there was only Mexico to deal with.

Relations between the two countries had been strained by the Texan independence movement, in which American citizens who moved to Mexico to settle its northern state of Coahuila y Tejas decided, after a short residence, to create an independent state there called Texas. The Mexican government responded in 1829 by levying a property tax, putting high taxes on American imports, and prohibiting slavery. Because Americans in Coahuila y Tejas outnumbered native Mexicans, and because internal political strife in Mexico made it difficult to fully command the northern states, they were able to ignore those laws, particularly the one against slaveholding. But when General Antonio López de Santa Anna became dictator of Mexico in 1834, he was determined to bring Coahuila y Tejas firmly back under Mexican control, and when the Texans declared their independence in 1836, Santa Anna traveled north to squash them.

Santa Anna’s defeat at the Battle of San Jacinto seemed to leave the Texans free to declare their independence. They did so, claiming all the territory in yellow on the map below (courtesy of Wikipedia), which they actually had settled, and then all the land in green as well, which they had not, and which, as you see, extended all the way north into Wyoming.

Because of the unsettled state of Texas, with its disputed borders and no official treaty with Mexico stating that it gave up Coahuila y Tejas, the U.S. was relatively slow to move when Texans made it clear they wanted to join the Union. The biggest potential problem was Texas’ claim to the Rio Grande as its western border which, as you can see, cut deeply into Mexico. U.S. politicians realized Mexico would not accept the U.S. annexing a new state that claimed so much Mexican soil as its own. When Texas was brought into the Union, in 1845, no mention of the Rio Grande border was made, and the U.S. made no formal claim to the land up to the river.

Still, Mexico was outraged with the annexation of Texas by the United States. Mexico had never officially ceded Coahuila y Tejas to the Texans. It was both the disastrous political instability in Mexico City and pressure from Britain and France, both of which had recognized Texas as a U.S. state, that kept the nation from immediately marching the full force of the army into its northern state and reclaiming it. Mexico did not declare war, but did break off diplomatic relations with the U.S.

In response, President Polk, who wanted the Rio Grande border, sent General Zachary Taylor to Texas to claim it. Again, Texas and the Rio Grande were just a means to an end for Polk and for most Americans—controlling the western lands up to the Rio Grande was one step closer to owning the Pacific, and Upper California. An army launched from the Rio Grande could be in California much sooner and with much less difficulty than one launched from the Mississippi River.

This is made clear by the secret cash offer Polk made to President José Joaquín de Herrera on November 10, 1845: $25 million for the lands up to the Rio Grande, and also for Upper California and Santa Fe de Nuevo Mexico U.S. forgiveness of a $3 million debt Mexico owed the U.S. and another $25-30 million to sweeten the deal.

It was too late. Mexicans were outraged when the deal was made public. They would not be bought. National honor was at stake. President Herrera was accused of treason for having entertained Polk’s representative and was deposed. The new government under General Mariano Paredes y Arrillaga stated its intention to re-claim Texas and retain all of Mexico’s northern states.

Polk ordered Taylor to take his army to the Rio Grande—into Mexico itself—and ignored Mexican demands to withdraw. This invasion sent the Mexican army north, and in April 1846 sixteen American soldiers on a patrol were killed by Mexican cavalry at the Nueces River. The Nueces, as you can see on the map, is just north of the Rio Grande in the boot of modern-day Texas and was the actual border of Texas (unlike the Rio Grande, which was the Texans’ desired border). Polk went to Congress on May 11 and stated that since the attack had occurred on the Nueces, officially U.S. territory because it was the actual State of Texas, Mexico had “shed American blood upon American soil”. Polk asked Congress to declare war, which it did on May 13th.

Mexico was likely irritated to hear the Nueces righteously claimed as American soil, since again there had never been a signed treaty handing over its northern state to the Texans or to the U.S. It declared war on July 7.

The debate in the U.S. Congress over whether to declare war fell along party lines—Whigs being mostly against it, Democrats being mostly for it. This sounds familiar to us today, but it was not the norm back then (see The Birth of Red and Blue States for more on this.) The Democrats were becoming more identified with Southern slaveholding interests. They wanted to fight for Texas, and the rest of northern Mexico, to make more slave states, and to bolster the slave-state population. Pro-slavery Americans worried that their influence was shrinking as the west was won in more northern areas. The free North was expanding faster than the slave South. If stalwartly slave Texas could be secured and substantially expanded west, it would be easy to continue the westward drive of slavery through what would become New Mexico and part of Arizona (Santa Fe de Nuevo Mexico) and the great prize of California itself.

The Whigs were becoming more identified with Northern free state interests, and knew exactly why the Southern Democrats were so eager to go to war. In the end, however, the Whigs were not united enough to challenge the Southern Democrats on the slavery issue, or to resist the war fever that swept Washington. They also longed to annex California, the most desired land in the west, and so they voted for war.


Mexico after independence Edit

Mexico obtained independence from the Spanish Empire with the Treaty of Córdoba in 1821 after a decade of conflict between the royal army and insurgents for independence, with no foreign intervention. The conflict ruined the silver-mining districts of Zacatecas and Guanajuato, so that Mexico began as a sovereign nation with its future financial stability from its main export destroyed. Mexico briefly experimented with monarchy but became a republic in 1824. This government was characterized by instability, [13] leaving it ill-prepared for a major international conflict when war broke out with the U.S. in 1846. Mexico had successfully resisted Spanish attempts to reconquer its former colony in the 1820s and resisted the French in the so-called Pastry War of 1838, but the secessionists' success in Texas and the Yucatan against the centralist government of Mexico showed the weakness of the Mexican government, which changed hands multiple times. The Mexican military and the Catholic Church in Mexico, both privileged institutions with conservative political views, were stronger politically than the Mexican state.

U.S. expansionism Edit

Since the early 19th century, the U.S. sought to expand its territory. Jefferson's Louisiana Purchase from France in 1803 gave Spain and the U.S. an undefined border. The young and weak U.S. fought the War of 1812 with Britain, with the U.S. launching an unsuccessful invasion of British Canada and Britain launching an equally unsuccessful counter-invasion. Some boundary issues were solved between the U.S. and Spain with the Adams-Onis Treaty of 1818. U.S. negotiator John Quincy Adams wanted clear possession of East Florida and establishment of U.S. claims above the 42nd parallel, while Spain sought to limit U.S. expansion into what is now the American Southwest. The U.S. then sought to purchase territory from Mexico, starting in 1825. U.S. President Andrew Jackson made a sustained effort to acquire northern Mexican territory, with no success. [14]

Historian Peter Guardino states that in the war "the greatest advantage the United States had was its prosperity." [15] Economic prosperity contributed to political stability in the U.S. Unlike Mexico's financial precariousness, the U.S. was a prosperous country with major resource endowments that Mexico lacked. Its war of independence had taken place generations earlier and was a relatively short conflict that ended with French intervention on the side of the 13 colonies. After independence, the U.S. grew rapidly and expanded westward, marginalizing and displacing Native Americans as settlers cleared land and established farms. With the Industrial Revolution across the Atlantic increasing the demand for cotton for textile factories, there was a large external market of a valuable commodity produced by slave labor in the southern states. This demand helped fuel expansion into northern Mexico. Although there were political conflicts in the U.S., they were largely contained by the framework of the constitution and did not result in revolution or rebellion by 1846, but rather by sectional political conflicts. The expansionism of the U.S. was driven in part by the need to acquire new territory for economic reasons, in particular, as cotton exhausted the soil in areas of the south, new lands had to be brought under cultivation to supply the demand for it. Northerners in the U.S. sought to develop the country's existing resources and expand the industrial sector without expanding the nation's territory. The existing balance of sectional interests would be disrupted by the expansion of slavery into new territory. The Democratic Party strongly supported expansion, so it is not by chance that the U.S. went to war with Mexico under Democratic President James K. Polk. [16]

Instability in northern Mexico Edit

Neither colonial Mexico nor the newly sovereign Mexican state effectively controlled Mexico's far north and west. Mexico's military and diplomatic capabilities declined after it attained independence from Spain in 1821 and left the northern one-half of the country vulnerable to attacks by Comanche, Apache, and Navajo Native Americans. [17] The Comanche, in particular, took advantage of the weakness of the Mexican state to undertake large-scale raids hundreds of miles into the country to acquire livestock for their own use and to supply an expanding market in Texas and the U.S. [18]

The northern area of Mexico was sparsely settled because of its climate and topography. It was mainly desert with little rainfall so that sedentary agriculture never developed there during the pre-Hispanic or colonial periods. During the colonial era (1521–1821) it had not been well controlled politically. After independence, Mexico contended with internal struggles that sometimes verged on civil war, and the situation on the northern frontier was not a high priority for the government in central Mexico. In northern Mexico, the end of Spanish rule was marked by the end of financing for presidios and for gifts to Native Americans to maintain the peace. The Comanche and Apache were successful in raiding for livestock and looting much of northern Mexico outside the scattered cities. The raids after 1821 resulted in the death of many Mexicans, halted most transportation and communications, and decimated the ranching industry that was a mainstay of the northern economy. As a result, the demoralized civilian population of northern Mexico put up little resistance to the invading U.S. army. [19]

Distance and hostile activity from Native Americans also made communications and trade between the heartland of Mexico and provinces such as Alta California and New Mexico difficult. As a result, New Mexico was dependent on the overland Santa Fe Trail trade with the United States at the outbreak of the war. [20]

The Mexican government's policy of settlement of U.S. citizens in its province of Tejas was aimed at expanding control into Comanche lands, the Comancheria. Instead of settlement occurring in the dangerous central and western parts of the province, people settled in East Texas, which held rich farmland contiguous to the southern U.S. slave states. As settlers poured in from the U.S., the Mexican government discouraged further settlement with its 1829 abolition of slavery.

Foreign designs on California Edit

During the Spanish colonial era, the Californias (i.e., the Baja California peninsula and Alta California) were sparsely settled. After Mexico became independent, it shut down the missions and reduced its military presence. In 1842, the U.S. minister in Mexico, Waddy Thompson Jr., suggested Mexico might be willing to cede Alta California to the U.S. to settle debts, saying: "As to Texas, I regard it as of very little value compared with California, the richest, the most beautiful, and the healthiest country in the world . with the acquisition of Upper California we should have the same ascendency on the Pacific . France and England both have had their eyes upon it." [21]

U.S. President John Tyler's administration suggested a tripartite pact to settle the Oregon boundary dispute and provide for the cession of the port of San Francisco from Mexico. Lord Aberdeen declined to participate but said Britain had no objection to U.S. territorial acquisition there. [22] The British minister in Mexico, Richard Pakenham, wrote in 1841 to Lord Palmerston urging "to establish an English population in the magnificent Territory of Upper California", saying that "no part of the World offering greater natural advantages for the establishment of an English colony . by all means desirable . that California, once ceasing to belong to Mexico, should not fall into the hands of any power but England . there is some reason to believe that daring and adventurous speculators in the United States have already turned their thoughts in this direction." By the time the letter reached London, though, Sir Robert Peel's Tory government, with its Little England policy, had come to power and rejected the proposal as expensive and a potential source of conflict. [23] [24]

A significant number of influential Californios supported annexation, either by the United States or by the United Kingdom. Pío de Jesús Pico IV, the last governor of Alta California, supported British annexation. [25]

Texas revolution, republic, and U.S. annexation Edit

In 1800, Spain's colonial province of Texas (Tejas) had few inhabitants, with only about 7,000 non-Indian settlers. [26] The Spanish crown developed a policy of colonization to more effectively control the territory. After independence, the Mexican government implemented the policy, granting Moses Austin, a banker from Missouri, a large tract of land in Texas. Austin died before he could bring his plan of recruiting American settlers for the land to fruition, but his son, Stephen F. Austin, brought over 300 American families into Texas. [27] This started the steady trend of migration from the United States into the Texas frontier. Austin's colony was the most successful of several colonies authorized by the Mexican government. The Mexican government intended the new settlers to act as a buffer between the Tejano residents and the Comanches, but the non-Hispanic colonists tended to settle in areas with decent farmland and trade connections with Louisiana rather than farther west where they would have been an effective buffer against the Indians.

In 1829, because of the large influx of American immigrants, the non-Hispanic outnumbered native Spanish speakers in Texas. President Vicente Guerrero, a hero of Mexican independence, moved to gain more control over Texas and its influx of non-Hispanic colonists from the southern U.S. and discourage further immigration by abolishing slavery in Mexico. [26] [28] The Mexican government also decided to reinstate the property tax and increase tariffs on shipped American goods. The settlers and many Mexican businessmen in the region rejected the demands, which led to Mexico closing Texas to additional immigration, which continued from the United States into Texas illegally.

In 1834, Mexican conservatives seized the political initiative, and General Antonio López de Santa Anna became the centralist president of Mexico. The conservative-dominated Congress abandoned the federal system, replacing it with a unitary central government that removed power from the states. Leaving politics to those in Mexico City, General Santa Anna led the Mexican army to quash the semi-independence of Texas. He had done that in Coahuila (in 1824, Mexico had merged Texas and Coahuila into the enormous state of Coahuila y Tejas). Austin called Texians to arms and they declared independence from Mexico in 1836. After Santa Anna defeated the Texians in the Battle of the Alamo, he was defeated by the Texian Army commanded by General Sam Houston and was captured at the Battle of San Jacinto he signed a treaty with Texas President David Burnet to allow Texas to plead its case for independence with the Mexican government but did not commit himself or Mexico to anything beyond that. He negotiated under duress and as a captive, and therefore had no standing to commit Mexico to a treaty. The Mexican Congress did not ratify it. [29] Although Mexico did not recognize Texas independence, Texas consolidated its status as an independent republic and received official recognition from Britain, France, and the United States, which all advised Mexico not to try to reconquer the new nation. Most Texians wanted to join the United States, but the annexation of Texas was contentious in the U.S. Congress, where Whigs and Abolitionists were largely opposed, although neither group went so far as to deny funds for the war. [30] : 150–155 In 1845, Texas agreed to the offer of annexation by the U.S. Congress and became the 28th state on December 29, 1845, which set the stage for the conflict with Mexico. [31]

Nueces Strip Edit

By the Treaties of Velasco made after Texans captured General Santa Ana after the Battle of San Jacinto, the southern border of Texas was placed at the "Rio Grande del Norte." The Texans claimed this placed the southern border at the modern Rio Grande. The Mexican government disputed this placement on two grounds: first, it rejected the idea of Texas independence and second, it claimed that the Rio Grande in the treaty was actually the Nueces River, since the current Rio Grande has always been called "Rio Bravo" in Mexico. The latter claim belied the full name of the river in Mexico, however: "Rio Bravo del Norte." The ill-fated Texan Santa Fe Expedition of 1841 attempted to realize the claim to New Mexican territory east of the Rio Grande, but its members were captured by the Mexican Army and imprisoned. Reference to the Rio Grande boundary of Texas was omitted from the U.S. Congress's annexation resolution to help secure passage after the annexation treaty failed in the Senate. President Polk claimed the Rio Grande boundary, and when Mexico sent forces over the Rio Grande, this provoked a dispute. [32]

Polk's gambits Edit

In July 1845, Polk sent General Zachary Taylor to Texas, and by October, Taylor commanded 3,500 Americans on the Nueces River, ready to take by force the disputed land. Polk wanted to protect the border and also coveted for the U.S. the continent clear to the Pacific Ocean. At the same time, Polk wrote to the American consul in the Mexican territory of Alta California, disclaiming American ambitions in California but offering to support independence from Mexico or voluntary accession to the United States, and warning that the United States would oppose any European attempts to take over. [32]

To end another war scare with the United Kingdom over the Oregon Country, Polk signed the Oregon Treaty dividing the territory, angering Northern Democrats who felt he was prioritizing Southern expansion over Northern expansion.

In the winter of 1845–46, the federally commissioned explorer John C. Frémont and a group of armed men appeared in Alta California. After telling the Mexican governor and the American Consul Larkin he was merely buying supplies on the way to Oregon, he instead went to the populated area of California and visited Santa Cruz and the Salinas Valley, explaining he had been looking for a seaside home for his mother. [33] Mexican authorities became alarmed and ordered him to leave. Frémont responded by building a fort on Gavilan Peak and raising the American flag. Larkin sent word that Frémont's actions were counterproductive. Frémont left California in March but returned to California and took control of the California Battalion following the outbreak of the Bear Flag Revolt in Sonoma. [34]

In November 1845, Polk sent John Slidell, a secret representative, to Mexico City with an offer to the Mexican government of $25 million for the Rio Grande border in Texas and Mexico's provinces of Alta California and Santa Fe de Nuevo México. U.S. expansionists wanted California to thwart any British interests in the area and to gain a port on the Pacific Ocean. Polk authorized Slidell to forgive the $3 million owed to U.S. citizens for damages caused by the Mexican War of Independence and pay another $25 to $30 million for the two territories. [35] [36]

Mexico's response Edit

Mexico was neither inclined nor able to negotiate. In 1846 alone, the presidency changed hands four times, the war ministry six times, and the finance ministry sixteen times. [37] Despite that, Mexican public opinion and all political factions agreed that selling the territories to the United States would tarnish the national honor. [38] [39] Mexicans who opposed direct conflict with the United States, including President José Joaquín de Herrera, were viewed as traitors. [40] Military opponents of de Herrera, supported by populist newspapers, considered Slidell's presence in Mexico City an insult. When de Herrera considered receiving Slidell to settle the problem of Texas annexation peacefully, he was accused of treason and deposed. After a more nationalistic government under General Mariano Paredes y Arrillaga came to power, it publicly reaffirmed Mexico's claim to Texas [40] Slidell, convinced that Mexico should be "chastised", returned to the U.S. [41]

Challenges in Mexico Edit

Mexican Army Edit

The Mexican Army emerged from the war of independence as a weak and divided force. Only 7 of the 19 states that formed the Mexican federation sent soldiers, armament, and money for the war effort, as the young Republic had not yet developed a sense of a unifying, national identity. [42] Mexican soldiers were not easily melded into an effective fighting force. Santa Anna said, "the leaders of the army did their best to train the rough men who volunteered, but they could do little to inspire them with patriotism for the glorious country they were honored to serve." [43] According to the leading Mexican conservative politician, Lucas Alamán, the "money spent on arming Mexican troops merely enabled them to fight each other and 'give the illusion' that the country possessed an army for its defense." [44] However, an officer criticized Santa Anna's training of troops, "The cavalry was drilled only in regiments. The artillery hardly ever maneuvered and never fired a blank shot. The general in command was never present on the field of maneuvers, so that he was unable to appreciate the respective qualities of the various bodies under his command . If any meetings of the principal commanding officers were held to discuss the operations of the campaign, it was not known, nor was it known whether any plan of campaign had been formed." [45]

At the beginning of the war, Mexican forces were divided between the permanent forces (permanentes) and the active militiamen (activos). The permanent forces consisted of 12 regiments of infantry (of two battalions each), three brigades of artillery, eight regiments of cavalry, one separate squadron and a brigade of dragoons. The militia amounted to nine infantry and six cavalry regiments. In the northern territories, presidial companies (presidiales) protected the scattered settlements. [46] Since Mexico fought the war on its home territory, a traditional support system for troops were women, known as soldaderas. They did not participate in conventional fighting on battlefields, but some soldaderas joined the battle alongside the men. These women were involved in fighting during the defense of Mexico City and Monterey. Some women such as Dos Amandes and María Josefa Zozaya would be remembered as heroes. [47]

The Mexican army was using surplus British muskets (such as the Brown Bess), left over from the Napoleonic Wars. While at the beginning of the war most American soldiers were still equipped with the very similar Springfield 1816 flintlock muskets, more reliable caplock models gained large inroads within the rank and file as the conflict progressed. Some U.S. troops carried radically modern weapons that gave them a significant advantage over their Mexican counterparts, such as the Springfield 1841 rifle of the Mississippi Rifles and the Colt Paterson revolver of the Texas Rangers. In the later stages of the war, the U.S. Mounted Rifles were issued Colt Walker revolvers, of which the U.S. Army had ordered 1,000 in 1846. Most significantly, throughout the war, the superiority of the U.S. artillery often carried the day. While technologically Mexican and American artillery operated on the same plane, U.S. army training, as well as the quality and reliability of their logistics, gave U.S. guns and cannoneers a significant edge. [ citation needed ]

In his 1885 memoirs, former US President Ulysses Grant (himself a veteran of the Mexican war) attributed Mexico's defeat to the poor quality of their army, writing:

"The Mexican army of that day was hardly an organization. The private soldier was picked from the lower class of the inhabitants when wanted his consent was not asked he was poorly clothed, worse fed, and seldom paid. He was turned adrift when no longer wanted. The officers of the lower grades were but little superior to the men. With all this I have seen as brave stands made by some of these men as I have ever seen made by soldiers. Now Mexico has a standing army larger than the United States. They have a military school modeled after West Point. Their officers are educated and, no doubt, very brave. The Mexican war of 1846–8 would be an impossibility in this generation." [48]

Political divisions Edit

There were significant political divisions in Mexico, but Mexicans were united in their opposition to the foreign aggression and stood for Mexico. Political differences seriously impeded Mexicans in the conduct of the war, but there was no disunity on their national stance. [49] Inside Mexico, the conservative centralistas and liberal federalists vied for power, and at times these two factions inside Mexico's military fought each other rather than the invading U.S. Army. Santa Anna bitterly remarked, "However shameful it may be to admit this, we have brought this disgraceful tragedy upon ourselves through our interminable in-fighting." [50]

During the conflict, presidents held office for a period of months, sometimes just weeks, or even days. Just before the outbreak of the war, liberal General José Joaquín de Herrera was president (December 1844 – December 1845) and willing to engage in talks so long as he did not appear to be caving to the U.S., but he was accused by many Mexican factions of selling out his country (vendepatria) for considering it. [51] He was overthrown by Conservative Mariano Paredes (December 1845 – July 1846), who left the presidency to fight the invading U.S. Army and was replaced by his vice president Nicolás Bravo (28 July 1846 – 4 August 1846). The conservative Bravo was overthrown by federalist liberals who re-established the federal Constitution of 1824. José Mariano Salas (6 August 1846 – 23 December 1846) served as president and held elections under the restored federalist system. General Antonio López de Santa Anna won those elections, but as was his practice, he left the administration to his vice president, who was again liberal Valentín Gómez Farías (23 December 1846 – 21 March 1847). In February 1847, conservatives rebelled against the liberal government's attempt to take Church property to fund the war effort. In the Revolt of the Polkos, the Catholic Church and conservatives paid soldiers to rise against the liberal government. [52] Santa Anna had to leave his campaign to return to the capital to sort out the political mess.

Santa Anna briefly held the presidency again, from 21 March 1847 – 2 April 1847. His troops were deprived of support that would allow them to continue the fight. The conservatives demanded the removal of Gómez Farías, and this was accomplished by abolishing the office of vice president. Santa Anna returned to the field, replaced in the presidency by Pedro María de Anaya (2 April 1847 – 20 May 1847). Santa Anna returned to the presidency on 20 May 1847 when Anaya left to fight the invasion, serving until 15 September 1847. Preferring the battlefield to administration, Santa Anna left office again, leaving the office to Manuel de la Peña y Peña (16 September 1847 – 13 November 1847).

With U.S. forces occupying the Mexican capital and much of the heartland, negotiating a peace treaty was an exigent matter, and Peña y Peña left office to do that. Pedro María Anaya returned to the presidency on 13 November 1847 – 8 January 1848. Anaya refused to sign any treaty that ceded land to the U.S., despite the situation on the ground with Americans occupying the capital, Peña y Peña resumed the presidency 8 January 1848 – 3 June 1848, during which time the Treaty of Guadalupe Hidalgo was signed, bringing the war to an end.

Challenges in the United States Edit

United States Army Edit

Polk had pledged to seek expanded territory in Oregon and Texas, as part of his campaign in 1844, but the regular army was not sufficiently large to sustain extended conflicts on two fronts. The Oregon dispute with Britain was settled peaceably by treaty, allowing U.S. forces to concentrate on the southern border.

The war was fought by regiments of regulars and various regiments, battalions, and companies of volunteers from the different states of the Union as well as Americans and some Mexicans in California and New Mexico. On the West Coast, the U.S. Navy fielded a battalion of sailors, in an attempt to recapture Los Angeles. [53] Although the U.S. Army and Navy were not large at the outbreak of the war, the officers were generally well trained and the numbers of enlisted men fairly large compared to Mexico's. At the beginning of the war, the U.S. Army had eight regiments of infantry (three battalions each), four artillery regiments and three mounted regiments (two dragoons, one of mounted rifles). These regiments were supplemented by 10 new regiments (nine of infantry and one of cavalry) raised for one year of service by the act of Congress from February 11, 1847. [54]

Although Polk hoped to avoid a protracted war over Texas, the extended conflict stretched regular army resources, necessitating the recruitment of volunteers with short-term enlistments. Some enlistments were for a year, but others were for 3 or 6 months. [55] The best volunteers signed up for a year's service in the summer of 1846, with their enlistments expiring just when General Winfield Scott's campaign was poised to capture Mexico City. Many did not re-enlist, deciding that they would rather return home than place themselves in harm's way of disease, threat of death or injury on the battlefield, or in guerrilla warfare. Their patriotism was doubted by some in the U.S., but they were not counted as deserters. [56] The volunteers were far less disciplined than the regular army, with many committing attacks on the civilian population, sometimes stemming from anti-Catholic and anti-Mexican racial bias. [57] Soldiers' memoirs describe cases of looting and murder of Mexican civilians, mostly by volunteers. One officer's diary records: "We reached Burrita about 5 pm, many of the Louisiana volunteers were there, a lawless drunken rabble. They had driven away the inhabitants, taken possession of their houses, and were emulating each other in making beasts of themselves." [58] John L. O'Sullivan, a vocal proponent of Manifest Destiny, later recalled "The regulars regarded the volunteers with importance and contempt . [The volunteers] robbed Mexicans of their cattle and corn, stole their fences for firewood, got drunk, and killed several inoffensive inhabitants of the town in the streets." Many of the volunteers were unwanted and considered poor soldiers. The expression "Just like Gaines's army" came to refer to something useless, the phrase having originated when a group of untrained and unwilling Louisiana troops was rejected and sent back by General Taylor at the beginning of the war. [59]

In his 1885 memoirs, Ulysses Grant assesses the U.S. armed forces facing Mexico more favorably.

The victories in Mexico were, in every instance, over vastly superior numbers. There were two reasons for this. Both General Scott and General Taylor had such armies as are not often got together. At the battles of Palo Alto and Resaca-de-la-Palma, General Taylor had a small army, but it was composed exclusively of regular troops, under the best of drill and discipline. Every officer, from the highest to the lowest, was educated in his profession, not at West Point necessarily, but in the camp, in garrison, and many of them in Indian wars. The rank and file were probably inferior, as material out of which to make an army, to the volunteers that participated in all the later battles of the war but they were brave men, and then drill and discipline brought out all there was in them. A better army, man for man, probably never faced an enemy than the one commanded by General Taylor in the earliest two engagements of the Mexican war. The volunteers who followed were of better material, but without drill or discipline at the start. They were associated with so many disciplined men and professionally educated officers, that when they went into engagements it was with a confidence they would not have felt otherwise. They became soldiers themselves almost at once. All these conditions we would enjoy again in case of war. [60]

Political divisions Edit

The U.S. had been an independent country since the American Revolution, and it was a strongly divided country along sectional lines. Enlarging the country, particularly through armed combat against a sovereign nation, deepened sectional divisions. Polk had narrowly won the popular vote in the 1844 presidential election and decisively won the Electoral College, but with the annexation of Texas in 1845 and the outbreak of war in 1846, Polk's Democrats lost the House of Representatives to the Whig Party, which opposed the war. Unlike Mexico, which had weak formal institutions of governance and the regular intervention of the military in politics and multiple changes of government, the U.S. generally kept its political divisions within the bounds of the institutions of governance.

Texas Campaign Edit

Thornton Affair Edit

President Polk ordered General Taylor and his forces south to the Rio Grande. Taylor ignored Mexican demands to withdraw to the Nueces. He constructed a makeshift fort (later known as Fort Brown/Fort Texas) on the banks of the Rio Grande opposite the city of Matamoros, Tamaulipas. [61]

The Mexican forces prepared for war. On April 25, 1846, a 2,000-man Mexican cavalry detachment attacked a 70-man U.S. patrol commanded by Captain Seth Thornton, which had been sent into the contested territory north of the Rio Grande and south of the Nueces River. In the Thornton Affair, the Mexican cavalry routed the patrol, killing 11 American soldiers and capturing 52. [62]

Siege of Fort Texas Edit

A few days after the Thornton Affair, the Siege of Fort Texas began on May 3, 1846. Mexican artillery at Matamoros opened fire on Fort Texas, which replied with its own guns. The bombardment continued for 160 hours [63] and expanded as Mexican forces gradually surrounded the fort. Thirteen U.S. soldiers were injured during the bombardment, and two were killed. [63] Among the dead was Jacob Brown, after whom the fort was later named. [64]

Battle of Palo Alto Edit

On May 8, 1846, Zachary Taylor and 2,400 troops arrived to relieve the fort. [65] However, General Arista rushed north with a force of 3,400 and intercepted him about 5 miles (8 km) north of the Rio Grande River, near modern-day Brownsville, Texas. The U.S. Army employed "flying artillery", their term for horse artillery, a mobile light artillery mounted on horse carriages with the entire crew riding horses into battle. The fast-firing artillery and highly mobile fire support had a devastating effect on the Mexican army. In contrast to the "flying artillery" of the Americans, the Mexican cannons at the Battle of Palo Alto had lower-quality gunpowder that fired at velocities slow enough to make it possible for American soldiers to dodge artillery rounds. [66] The Mexicans replied with cavalry skirmishes and their own artillery. The U.S. flying artillery somewhat demoralized the Mexican side, and seeking terrain more to their advantage, the Mexicans retreated to the far side of a dry riverbed (resaca) during the night and prepared for the next battle. It provided a natural fortification, but during the retreat, Mexican troops were scattered, making communication difficult. [63]

Battle of Resaca de la Palma Edit

During the Battle of Resaca de la Palma on May 9, 1846, the two sides engaged in fierce hand-to-hand combat. The U.S. Cavalry managed to capture the Mexican artillery, causing the Mexican side to retreat—a retreat that turned into a rout. [63] Fighting on unfamiliar terrain, his troops fleeing in retreat, Arista found it impossible to rally his forces. Mexican casualties were significant, and the Mexicans were forced to abandon their artillery and baggage. Fort Brown inflicted additional casualties as the withdrawing troops passed by the fort, and additional Mexican soldiers drowned trying to swim across the Rio Grande. [67] Taylor crossed the Rio Grande and began his series of battles in Mexican territory.

Declarations of war, May 1846 Edit

Polk received word of the Thornton Affair, which, added to the Mexican government's rejection of Slidell, Polk believed, constituted a casus belli. [68] His message to Congress on May 11, 1846, claimed that "Mexico has passed the boundary of the United States, has invaded our territory and shed American blood upon American soil." [69] [70]

The U.S. Congress approved the declaration of war on May 13, 1846, after a few hours of debate, with southern Democrats in strong support. Sixty-seven Whigs voted against the war on a key slavery amendment, [71] but on the final passage only 14 Whigs voted no, [71] including Rep. John Quincy Adams. Later, a freshman Whig Congressman from Illinois, Abraham Lincoln, challenged Polk's assertion that American blood had been shed on American soil, calling it "a bold falsification of history." [72] [73]

Regarding the beginning of the war, Ulysses S. Grant, who had opposed the war but served as an army lieutenant in Taylor's Army, claims in his Personal Memoirs (1885) that the main goal of the U.S. Army's advance from Nueces River to the Rio Grande was to provoke the outbreak of war without attacking first, to debilitate any political opposition to the war.

The presence of United States troops on the edge of the disputed territory farthest from the Mexican settlements, was not sufficient to provoke hostilities. We were sent to provoke a fight, but it was essential that Mexico should commence it. It was very doubtful whether Congress would declare war but if Mexico should attack our troops, the Executive could announce, "Whereas, war exists by the acts of, etc.," and prosecute the contest with vigor. Once initiated there were but few public men who would have the courage to oppose it. . Mexico showing no willingness to come to the Nueces to drive the invaders from her soil, it became necessary for the "invaders" to approach to within a convenient distance to be struck. Accordingly, preparations were begun for moving the army to the Rio Grande, to a point near Matamoras [sic]. It was desirable to occupy a position near the largest centre of population possible to reach, without absolutely invading territory to which we set up no claim whatever. [74]

In Mexico, although President Paredes issued a manifesto on May 23, 1846, and a declaration of a defensive war on April 23, both of which are considered by some the de facto start of the war, Mexico officially declared war by Congress on July 7, 1846. [75] : 148

General Santa Anna's return Edit

Mexico's defeats at Palo Alto and Resaca de la Palma set the stage for the return of Santa Anna, who at the outbreak of the war, was in exile in Cuba. He wrote to the government in Mexico City, stating he did not want to return to the presidency, but he would like to come out of exile in Cuba to use his military experience to reclaim Texas for Mexico. President Farías was driven to desperation. He accepted the offer and allowed Santa Anna to return. Unbeknownst to Farías, Santa Anna had secretly been dealing with U.S. representatives to discuss a sale of all contested territory to the U.S. at a reasonable price, on the condition that he be allowed back in Mexico through the U.S. naval blockades. Polk sent his own representative to Cuba, Alexander Slidell MacKenzie, to negotiate directly with Santa Anna. The negotiations were secret and there are no written records of the meetings, but there was some understanding that came out of the meetings. Polk asked Congress for $2 million to be used in negotiating a treaty with Mexico. The U.S. allowed Santa Anna to return to Mexico, lifting the Gulf Coast naval blockade. However, in Mexico, Santa Anna denied all knowledge of meeting with the U.S. representative or any offers or transactions. Rather than being Polk's ally, he pocketed any money given him and began to plan the defense of Mexico. The Americans were dismayed, including General Scott, as this was an unexpected result. "Santa Anna gloated over his enemies' naïveté: 'The United States was deceived in believing that I would be capable of betraying my mother country.'" [76] Santa Anna avoided getting involved in politics, dedicating himself to Mexico's military defense. While politicians attempted to reset the governing framework to a federal republic, Santa Anna left for the front to retake lost northern territory. Although Santa Anna was elected president in 1846, he refused to govern, leaving that to his vice president, while he sought to engage with Taylor's forces. With the restored federal republic, some states refused to support the national military campaign led by Santa Anna, who had fought with them directly in the previous decade. Santa Anna urged Vice President Gómez Farías to act as a dictator to get the men and materiel needed for the war. Gómez Farías forced a loan from the Catholic Church, but the funds were not available in time to support Santa Anna's army. [77]

Opposition to the war Edit

In the United States, increasingly divided by sectional rivalry, the war was a partisan issue and an essential element in the origins of the American Civil War. Most Whigs in the North and South opposed it [78] most Democrats supported it. [79] Southern Democrats, animated by a popular belief in Manifest Destiny, supported it in hope of adding slave-owning territory to the South and avoiding being outnumbered by the faster-growing North. John L. O'Sullivan, editor of the Democratic Review, coined this phrase in its context, stating that it must be "our manifest destiny to overspread the continent allotted by Providence for the free development of our yearly multiplying millions." [80]

Northern antislavery elements feared the expansion of the Southern Slave Power Whigs generally wanted to strengthen the economy with industrialization, not expand it with more land. Among the most vocal opposing the war in the House of Representatives was former U.S. President John Quincy Adams, a representative of Massachusetts. Adams had first voiced concerns about expanding into Mexican territory in 1836 when he opposed Texas annexation following its de facto independence from Mexico. He continued this argument in 1846 for the same reason. War with Mexico would add new slavery territory to the nation. When the question to go to war with Mexico came to a vote on 13 May 1846, Adams spoke a resounding "No!" in the chamber. Only 13 others followed his lead. Despite that opposition, he later voted for war appropriations. [30] : 151

Ex-slave Frederick Douglass opposed the war and was dismayed by the weakness of the anti-war movement. "The determination of our slave holding president, and the probability of his success in wringing from the people, men and money to carry it on, is made evident by the puny opposition arrayed against him. None seem willing to take their stand for peace at all risks." [81]

Polk was generally able to manipulate Whigs into supporting appropriations for the war but only once it had already started and then "clouding the situation with a number of false statements about Mexican actions." [82] Not everyone went along. Joshua Giddings led a group of dissenters in Washington D.C. He called the war with Mexico "an aggressive, unholy, and unjust war" and voted against supplying soldiers and weapons. He said: "In the murder of Mexicans upon their own soil, or in robbing them of their country, I can take no part either now or hereafter. The guilt of these crimes must rest on others. I will not participate in them." [83]

Fellow Whig Abraham Lincoln contested Polk's causes for the war. Polk had said that Mexico had "shed American blood upon American soil". Lincoln submitted eight "Spot Resolutions", demanding that Polk state the exact spot where Thornton had been attacked and American blood shed, and to clarify whether that location was American soil or if it had been claimed by Spain and Mexico. Lincoln, too, did not actually stop money for men or supplies in the war effort. [30] : 151

Whig Senator Thomas Corwin of Ohio gave a long speech indicting presidential war in 1847. In the Senate February 11, 1847, Whig leader Robert Toombs of Georgia declared: "This war is nondescript . We charge the President with usurping the war-making power . with seizing a country . which had been for centuries, and was then in the possession of the Mexicans. . Let us put a check upon this lust of dominion. We had territory enough, Heaven knew. [84] Democratic Representative David Wilmot introduced the Wilmot Proviso, which would prohibit slavery in new territory acquired from Mexico. Wilmot's proposal passed the House but not the Senate. [85] [86]

Northern abolitionists attacked the war as an attempt by slave-owners to strengthen the grip of slavery and thus ensure their continued influence in the federal government. Prominent artists and writers opposed the war, including James Russell Lowell, whose works on the subject "The Present Crisis" [87] and the satirical The Biglow Papers were immediately popular. [88] Transcendentalist writers Henry David Thoreau and Ralph Waldo Emerson also criticized the war. Thoreau, who served jail time for refusing to pay a tax that would support the war effort, turned a lecture into an essay now known as Civil Disobedience. Emerson was succinct, predicting that, "The United States will conquer Mexico, but it will be as a man who swallowed the arsenic which brings him down in turn. Mexico will poison us." Events proved him right, as arguments over the expansion of slavery in the lands seized from Mexico would fuel the drift to civil war just a dozen years later. [89] The New England Workingmen's Association condemned the war, and some Irish and German immigrants defected from the U.S. Army and formed the Saint Patrick's Battalion to fight for Mexico. [30] : 152–157

Support of the war Edit

Besides alleging that the actions of Mexican military forces within the disputed boundary lands north of the Rio Grande constituted an attack on American soil, the war's advocates viewed the territories of New Mexico and California as only nominally Mexican possessions with very tenuous ties to Mexico. They saw the territories as unsettled, ungoverned, and unprotected frontier lands, whose non-aboriginal population represented a substantial American component. Moreover, the territories were feared by Americans to be under imminent threat of acquisition by America's rival on the continent, the British.

President Polk reprised these arguments in his Third Annual Message to Congress on December 7, 1847. [90] He scrupulously detailed his administration's position on the origins of the conflict, the measures the U.S. had taken to avoid hostilities, and the justification for declaring war. He also elaborated upon the many outstanding financial claims by American citizens against Mexico and argued that, in view of the country's insolvency, the cession of some large portion of its northern territories was the only indemnity realistically available as compensation. This helped to rally congressional Democrats to his side, ensuring passage of his war measures and bolstering support for the war in the U.S.

U.S. journalism during the war Edit

The Mexican–American War was the first U.S. war that was covered by mass media, primarily the penny press, and was the first foreign war covered primarily by U.S. correspondents. [91] Press coverage in the United States was characterized by support for the war and widespread public interest and demand for coverage of the conflict. Mexican coverage of the war (both written by Mexicans and Americans based in Mexico) was affected by press censorship, first by the Mexican government and later by the American military.

Walt Whitman enthusiastically endorsed the war in 1846 and showed his disdainful attitude toward Mexico and boosterism for Manifest Destiny: "What has miserable, inefficient Mexico—with her superstition, her burlesque upon freedom, her actual tyranny by the few over the many—what has she to do with the great mission of peopling the new world with a noble race? Be it ours, to achieve that mission!" [92]

The coverage of the war was an important development in the U.S., with journalists as well as letter-writing soldiers giving the public in the U.S. "their first-ever independent news coverage of warfare from home or abroad." [93] During the war, inventions such as the telegraph created new means of communication that updated people with the latest news from the reporters on the scene. The most important of these was George Wilkins Kendall, a Northerner who wrote for the New Orleans Picayune, and whose collected Dispatches from the Mexican War constitute an important primary source for the conflict. [94] With more than a decade's experience reporting urban crime, the "penny press" realized the public's voracious demand for astounding war news. Moreover, Shelley Streetby demonstrates that the print revolution, which preceded the U.S.-Mexican War, made it possible for the distribution of cheap newspapers throughout the country. [95] This was the first time in U.S. history that accounts by journalists instead of opinions of politicians had great influence in shaping people's opinions about and attitudes toward a war. Along with written accounts of the war, war artists provided a visual dimension to the war at the time and immediately afterward. Carl Nebel's visual depictions of the war are well known. [96]

By getting constant reports from the battlefield, Americans became emotionally united as a community. News about the war caused extraordinary popular excitement. In the spring of 1846, news about Taylor's victory at Palo Alto brought up a large crowd that met in the cotton textile town of Lowell, Massachusetts. In Chicago, a large concourse of citizens gathered in April 1847 to celebrate the victory of Buena Vista. [97] New York celebrated the twin victories at Veracruz and Buena Vista in May 1847. Generals Taylor and Scott became heroes for their people and later became presidential candidates. Polk had pledged to be a one-term president, but his last official act was to attend Taylor's inauguration as president. [98]

New Mexico campaign Edit

After the declaration of war on May 13, 1846, United States Army General Stephen W. Kearny moved southwest from Fort Leavenworth, Kansas, in June 1846 with about 1,700 men in his Army of the West. Kearny's orders were to secure the territories Nuevo México and Alta California. [99]

In Santa Fe, Governor Manuel Armijo wanted to avoid battle, but on August 9, Colonel Diego Archuleta and militia officers Manuel Chaves and Miguel Pino forced him to muster a defense. [100] Armijo set up a position in Apache Canyon, a narrow pass about 10 miles (16 km) southeast of the city. [101] However, on August 14, before the American army was even in view, he decided not to fight. An American named James Magoffin claimed he had convinced Armijo and Archuleta to follow this course [102] an unverified story says he bribed Armijo. [103] When Pino, Chaves, and some of the militiamen insisted on fighting, Armijo ordered the cannon pointed at them. [100] The New Mexican army retreated to Santa Fe, and Armijo fled to Chihuahua.

Kearny and his troops encountered no Mexican forces when they arrived on August 15. Kearny and his force entered Santa Fe and claimed the New Mexico Territory for the United States without a shot fired. Kearny declared himself the military governor of the New Mexico Territory on August 18 and established a civilian government. American officers drew up a temporary legal system for the territory called the Kearny Code. [104]

Kearny then took the remainder of his army west to Alta California [99] he left Colonel Sterling Price in command of U.S. forces in New Mexico. He appointed Charles Bent as New Mexico's first territorial governor. Following Kearny's departure, dissenters in Santa Fe plotted a Christmas uprising. When the plans were discovered by the U.S. authorities, the dissenters postponed the uprising. They attracted numerous Indian allies, including Puebloans, who also wanted to push the Americans from the territory. On the morning of January 19, 1847, the insurrectionists began the revolt in Don Fernando de Taos, present-day Taos, New Mexico, which later gave it the name the Taos Revolt. They were led by Pablo Montoya, a New Mexican, and Tomás Romero, a Taos pueblo Indian also known as Tomasito (Little Thomas).

Romero led an Indian force to the house of Governor Charles Bent, where they broke down the door, shot Bent with arrows, and scalped him in front of his family. They moved on, leaving Bent still alive. With his wife Ignacia and children, and the wives of friends Kit Carson and Thomas Boggs, the group escaped by digging through the adobe walls of their house into the one next door. When the insurgents discovered the party, they killed Bent but left the women and children unharmed.

The next day a large armed force of approximately 500 New Mexicans and Pueblo attacked and laid siege to Simeon Turley's mill in Arroyo Hondo, several miles outside of Taos. Charles Autobees, an employee at the mill, saw the men coming. He rode to Santa Fe for help from the occupying U.S. forces. Eight to ten mountain men were left at the mill for defense. After a day-long battle, only two of the mountain men survived, John David Albert and Thomas Tate Tobin, Autobees' half-brother. Both escaped separately on foot during the night. The same day New Mexican insurgents killed seven American traders passing through the village of Mora. At most, 15 Americans were killed in both actions on January 20.

The U.S. military moved quickly to quash the revolt Colonel Price led more than 300 U.S. troops from Santa Fe to Taos, together with 65 volunteers, including a few New Mexicans, organized by Ceran St. Vrain, the business partner of William and Charles Bent. Along the way, the combined forces beat back a force of some 1,500 New Mexicans and Pueblo at Santa Cruz de la Cañada and at Embudo Pass. The insurgents retreated to Taos Pueblo, where they took refuge in the thick-walled adobe church. During the ensuing battle, the U.S. breached a wall of the church and directed cannon fire into the interior, inflicting many casualties and killing about 150 rebels. They captured 400 more men after close hand-to-hand fighting. Only seven Americans died in the battle. [105]

A separate force of U.S. troops under captains Israel R. Hendley and Jesse I. Morin campaigned against the rebels in Mora. The First Battle of Mora ended in a New Mexican victory. The Americans attacked again in the Second Battle of Mora and won, which ended their operations against Mora. New Mexican rebels engaged U.S. forces three more times in the following months. The actions are known as the Battle of Red River Canyon, the Battle of Las Vegas, and the Battle of Cienega Creek. After the U.S. forces won each battle, the New Mexicans and Indians ended open warfare. [ citation needed ]

California campaign Edit

Word of Congress' declaration of war reached California by August 1846. [106] American consul Thomas O. Larkin, stationed in Monterey, worked successfully during the events in that vicinity to avoid bloodshed between Americans and the Mexican military garrison commanded by General José Castro, the senior military officer in California. [107]

Captain John C. Frémont, leading a U.S. Army topographical expedition to survey the Great Basin, entered Sacramento Valley in December 1845. [108] Frémont's party was at Upper Klamath Lake in the Oregon Territory when it received word that war between Mexico and the U.S. was imminent [109] the party then returned to California. [110]

Mexico had issued a proclamation that unnaturalized foreigners were no longer permitted to have land in California and were subject to expulsion. [111] With rumors swirling that General Castro was massing an army against them, American settlers in the Sacramento Valley banded together to meet the threat. [112] On June 14, 1846, 34 American settlers seized control of the undefended Mexican government outpost of Sonoma to forestall Castro's plans. [113] One settler created the Bear Flag and raised it over Sonoma Plaza. Within a week, 70 more volunteers joined the rebels' force, [114] which grew to nearly 300 in early July. [115] This event, led by William B. Ide, became known as the Bear Flag Revolt.

On June 25, Frémont's party arrived to assist in an expected military confrontation. [116] San Francisco, then called Yerba Buena, was occupied by the Bear Flaggers on July 2. [117] On July 5, Frémont's California Battalion was formed by combining his forces with many of the rebels. [118]

Commodore John D. Sloat, commander of the U.S. Navy's Pacific Squadron, near Mazatlan, Mexico, had received orders to seize San Francisco Bay and blockade California ports when he was positive that war had begun. [119] Sloat set sail for Monterey, reaching it on July 1. [120] Sloat, upon hearing of the events in Sonoma and Frémont's involvement, erroneously believed Frémont to be acting on orders from Washington and ordered his forces to occupy Monterey on July 7 and raise the U.S. flag. [121] On July 9, 70 sailors and Marines landed at Yerba Buena and raised the American flag. Later that day in Sonoma, the Bear Flag was lowered, and the American flag was raised in its place. [122]

On Sloat's orders, Frémont brought 160 volunteers to Monterey, in addition to the California Battalion. [123] On July 15, Sloat transferred his command of the Pacific Squadron to Commodore Robert F. Stockton, who was more militarily aggressive. [124] He mustered the willing members of the California Battalion into military service with Frémont in command. [124] Stockton ordered Frémont to San Diego to prepare to move northward to Los Angeles. [125] As Frémont landed, Stockton's 360 men arrived in San Pedro. [126] General Castro and Governor Pío Pico wrote farewells and fled separately to the Mexican state of Sonora. [127]

Stockton's army entered Los Angeles unopposed on August 13, whereupon he sent a report to the secretary of state that "California is entirely free from Mexican dominion." [128] Stockton, however, left a tyrannical officer in charge of Los Angeles with a small force. [129] The Californios under the leadership of José María Flores, acting on their own and without federal help from Mexico, in the Siege of Los Angeles, forced the American garrison to retreat on September 29. [130] They also forced small U.S. garrisons in San Diego and Santa Barbara to flee. [131]

Captain William Mervine landed 350 sailors and Marines at San Pedro on October 7. [132] They were ambushed and repulsed at the Battle of Dominguez Rancho by Flores' forces in less than an hour. [133] Four Americans died, with 8 severely injured. Stockton arrived with reinforcements at San Pedro, which increased the American forces there to 800. [134] He and Mervine then set up a base of operations at San Diego. [135]

Meanwhile, Kearny and his force of about 115 men, who had performed a grueling march across the Sonoran Desert, crossed the Colorado River in late November 1846. [136] Stockton sent a 35-man patrol from San Diego to meet them. [137] On December 7, 100 lancers under General Andrés Pico (brother of the governor), tipped off and lying in wait, fought Kearny's army of about 150 at the Battle of San Pasqual, where 22 of Kearny's men (one of whom later died of wounds), including three officers, were killed in 30 minutes of fighting. [138] The wounded Kearny and his bloodied force pushed on until they had to establish a defensive position on "Mule Hill". [139] However, General Pico kept the hill under siege for four days until a 215-man American relief force arrived. [140]

Frémont and the 428-man California Battalion arrived in San Luis Obispo on December 14 [141] and Santa Barbara on December 27. [142] On December 28, a 600-man American force under Kearny began a 150-mile march to Los Angeles. [143] [144] Flores then moved his ill-equipped 500-man force to a 50-foot-high bluff above the San Gabriel River. [145] On January 8, 1847, the Stockton-Kearny army defeated the Californio force in the two-hour Battle of Rio San Gabriel. [146] [147] That same day, Frémont's force arrived at San Fernando. [148] The next day, January 9, the Stockton-Kearny forces fought and won the Battle of La Mesa. [149] On January 10, the U.S. Army entered Los Angeles to no resistance. [150]

On January 12, Frémont and two of Pico's officers agreed to terms for a surrender. [151] Articles of Capitulation were signed on January 13 by Frémont, Andrés Pico and six others at a ranch at Cahuenga Pass (modern-day North Hollywood). [151] This became known as the Treaty of Cahuenga, which marked the end of armed resistance in California. [151]

Pacific Coast campaign Edit

Entering the Gulf of California, Independence, Congress, and Cyane seized La Paz, then captured and burned the small Mexican fleet at Guaymas on October 19, 1847. Within a month, they cleared the gulf of hostile ships, destroying or capturing 30 vessels. Later, their sailors and Marines captured the port of Mazatlán on November 11, 1847. After upper California was secure, most of the Pacific Squadron proceeded down the California coast, capturing all major cities of the Baja California Territory and capturing or destroying nearly all Mexican vessels in the Gulf of California.

A Mexican campaign under Manuel Pineda Muñoz to retake the various captured ports resulted in several small clashes and two sieges in which the Pacific Squadron ships provided artillery support. U.S. garrisons remained in control of the ports. Following reinforcement, Lt. Col. Henry S. Burton marched out. His forces rescued captured Americans, captured Pineda, and on March 31 defeated and dispersed remaining Mexican forces at the Skirmish of Todos Santos, unaware that the Treaty of Guadalupe Hidalgo had been signed in February 1848 and a truce agreed to on March 6. When the U.S. garrisons were evacuated to Monterey following the treaty ratification, many Mexicans went with them: those who had supported the U.S. cause and had thought Lower California would also be annexed along with Upper California.

Northeastern Mexico Edit

Led by Zachary Taylor, 2,300 U.S. troops crossed the Rio Grande after some initial difficulties in obtaining river transport. His soldiers occupied the city of Matamoros, then Camargo (where the soldiery suffered the first of many problems with disease) and then proceeded south and besieged the city of Monterrey, Nuevo León. The hard-fought Battle of Monterrey resulted in serious losses on both sides. The U.S. light artillery was ineffective against the stone fortifications of the city, as the American forces attacked in frontal assaults. The Mexican forces under General Pedro de Ampudia repulsed Taylor's best infantry division at Fort Teneria. [152]

American soldiers, including many West Point graduates, had never engaged in urban warfare before, and they marched straight down the open streets, where they were annihilated by Mexican defenders well-hidden in Monterrey's thick adobe homes. [152] They quickly learned, and two days later, they changed their urban warfare tactics. Texan soldiers had fought in a Mexican city before (the Siege of Béxar in December 1835) and advised Taylor's generals that the Americans needed to "mouse hole" through the city's homes. They needed to punch holes in the side or roofs of the homes and fight hand to hand inside the structures. Mexicans called the Texas soldiers the Diabólicos Tejanos (the Devil Texans). [153] This method proved successful. [154] Eventually, these actions drove and trapped Ampudia's men into the city's central plaza, where howitzer shelling forced Ampudia to negotiate. Taylor agreed to allow the Mexican Army to evacuate and to an eight-week armistice in return for the surrender of the city. Taylor broke the armistice and occupied the city of Saltillo, southwest of Monterrey. Santa Anna blamed the loss of Monterrey and Saltillo on Ampudia and demoted him to command a small artillery battalion. Similarly, Polk blamed Taylor both for suffering heavy losses and failing to imprison Ampudia's entire force. Taylor's army was subsequently stripped of most of its troops in order to support the coming coastal operations by Scott against Veracruz and the Mexican heartland.

On February 22, 1847, having heard of this weakness from the written orders found on an ambushed U.S. scout, Santa Anna seized the initiative and marched Mexico's entire army north to fight Taylor with 20,000 men, hoping to win a smashing victory before Scott could invade from the sea. The two armies met and fought the largest battle of the war at the Battle of Buena Vista. Taylor, with 4,600 men, had entrenched at a mountain pass called La Angostura, or "the narrows", several miles south of Buena Vista ranch. Santa Anna, having little logistics to supply his army, suffered desertions all the long march north and arrived with only 15,000 men in a tired state.

Having demanded and been refused the surrender of the U.S. Army, Santa Anna's army attacked the next morning, using a ruse in the battle with the U.S forces. Santa Anna flanked the U.S. positions by sending his cavalry and some of his infantry up the steep terrain that made up one side of the pass, while a division of infantry attacked frontally to distract and draw out the U.S. forces along the road leading to Buena Vista. Furious fighting ensued, during which the U.S. troops were nearly routed but managed to cling to their entrenched position, thanks to the Mississippi Rifles, a volunteer regiment led by Jefferson Davis, who formed them into a defensive V formation. [155] The Mexicans had nearly broken the American lines at several points, but their infantry columns, navigating the narrow pass, suffered heavily from the American horse artillery, which fired point-blank canister shots to break up the attacks.

Initial reports of the battle, as well as propaganda from the Santanistas, credited the victory to the Mexicans, much to the joy of the Mexican populace, but rather than attack the next day and finish the battle, Santa Anna retreated, losing men along the way, having heard word of rebellion and upheaval in Mexico City. Taylor was left in control of part of northern Mexico, and Santa Anna later faced criticism for his withdrawal. Mexican and American military historians alike agree that the U.S. Army could likely have been defeated if Santa Anna had fought the battle to its finish. [156]

Polk mistrusted Taylor, who he felt had shown incompetence in the Battle of Monterrey by agreeing to the armistice. Taylor later used the Battle of Buena Vista as the centerpiece of his successful 1848 presidential campaign.

Northwestern Mexico Edit

Northwestern Mexico was essentially tribal Indian territory, but on November 21, 1846, the Bear Springs Treaty was signed, ending a large-scale insurrection by the Ute, Zuni, Moquis, and Navajo tribes. [157] In December 1846, after the successful conquest of New Mexico, part of Kearney's Army of the West, the First Missouri Mounted Volunteers, moved into modern-day northwest Mexico. They were led by Alexander W. Doniphan, continuing what ended up being a year-long 5,500 mile campaign. It was described as rivaling Xenophon's march across Anatolia during the Greco-Persian Wars. [158] [159] [160]

On Christmas day, they won the Battle of El Brazito, outside the modern-day El Paso, Texas. [161] On March 1, 1847, Doniphan occupied Chihuahua City. British consul John Potts did not want to allow Doniphan to search Governor Trías's mansion and unsuccessfully asserted it was under British protection. American merchants in Chihuahua wanted the American force to stay in order to protect their business. Major William Gilpin advocated a march on Mexico City and convinced a majority of officers, but Doniphan subverted this plan. Then in late April, Taylor ordered the First Missouri Mounted Volunteers to leave Chihuahua and join him at Saltillo. The American merchants either followed or returned to Santa Fe. Along the way, the townspeople of Parras enlisted Doniphan's aid against an Indian raiding party that had taken children, horses, mules, and money. [162] The Missouri Volunteers finally made their way to Matamoros, from which they returned to Missouri by water. [159]

The civilian population of northern Mexico offered little resistance to the American invasion, possibly because the country had already been devastated by Comanche and Apache Indian raids. Josiah Gregg, who was with the American army in northern Mexico, said "the whole country from New Mexico to the borders of Durango is almost entirely depopulated. The haciendas and ranchos have been mostly abandoned, and the people chiefly confined to the towns and cities." [163]

Southern Mexico Edit

Southern Mexico had a large indigenous population and was geographically distant from the capital, over which the central government had weak control. Yucatán in particular had closer ties to Cuba and to the United States than it did to central Mexico. On a number of occasions in the early era of the Mexican Republic, Yucatán seceded from the federation. There were also rivalries between regional elites, with one faction based in Mérida and the other in Campeche. These issues factored into the Mexican–American War, as the U. S. had designs on this part of the coast. [164]

The U.S. Navy contributed to the war by controlling the coast and clearing the way for U.S. troops and supplies, especially to Mexico's main port of Veracruz. Even before hostilities began in the disputed northern region, the U.S. Navy created a blockade. Given the shallow waters of that portion of the coast, the U.S. Navy needed ships with a shallow draft rather than large frigates. Since the Mexican Navy was almost non-existent, the U.S. Navy could operate unimpeded in gulf waters. [165] The U.S. fought two battles in Tabasco in October 1846 and in June 1847.

In 1847, the Maya revolted against the Mexican elites of the peninsula in a caste war known as the Caste War of Yucatan. Jefferson Davis, then a senator from Mississippi, argued in Congress that the president needed no further powers to intervene in Yucatan since the war with Mexico was underway. Davis's concern was strategic and part of his vision of Manifest Destiny, considering the Gulf of Mexico "a basin of water belonging to the United States" and "the cape of Yucatan and the island of Cuba must be ours". [166] In the end, the U.S. did not intervene in Yucatán, but it had figured in congressional debates about the Mexican–American War. At one point, the government of Yucatán petitioned the U.S. for protection during the Caste War, [167] but the U.S. did not respond.

Landings and siege of Veracruz Edit

Rather than reinforce Taylor's army for a continued advance, President Polk sent a second army under General Winfield Scott. Polk had decided that the way to bring the war to an end was to invade the Mexican heartland from the coast. General Scott's army was transported to the port of Veracruz by sea to begin an invasion to take the Mexican capital. [168] On March 9, 1847, Scott performed the first major amphibious landing in U.S. history in preparation for a siege. [169] A group of 12,000 volunteer and regular soldiers successfully offloaded supplies, weapons, and horses near the walled city using specially designed landing crafts. Included in the invading force were several future generals: Robert E. Lee, George Meade, Ulysses S. Grant, James Longstreet, and Thomas "Stonewall" Jackson.

Veracruz was defended by Mexican General Juan Morales with 3,400 men. Mortars and naval guns under Commodore Matthew C. Perry were used to reduce the city walls and harass defenders. The bombardment on March 24, 1847, opened in the walls of Veracruz a thirty-foot gap. [170] The defenders in the city replied with its own artillery, but the extended barrage destroyed the will of the Mexicans to fight against a numerically superior force, and they surrendered the city after 12 days under siege. U.S. troops suffered 80 casualties, while the Mexicans had around 180 killed and wounded, with hundreds of civilians killed. [171] During the siege, the U.S. soldiers began to fall victim to yellow fever.

Advance on Puebla Edit

Santa Anna allowed Scott's army to march inland, counting on yellow fever and other tropical diseases to take their toll before Santa Anna chose a place to engage the enemy. Mexico had used this tactic before, including when Spain attempted to reconquer Mexico in 1829. Disease could be a decisive factor in the war. Santa Anna was from Veracruz, so he was on his home territory, knew the terrain, and had a network of allies. He could draw on local resources to feed his ill-fed army and gain intelligence on the enemy's movement. From his experience in the northern battles on open terrain, Santa Anna sought to negate the U.S. Army's advantage of the use of artillery.

Santa Anna chose Cerro Gordo to engage, calculating it would have the maximum advantage for the Mexican forces. [172] Scott marched westward on April 2, 1847, toward Mexico City with 8,500 initially healthy troops, while Santa Anna set up a defensive position in a canyon around the main road and prepared fortifications. Santa Anna had entrenched with what the U.S. Army believed were 12,000 troops but in fact was around 9,000. [173] He had artillery trained on the road where he expected Scott to appear. However, Scott had sent 2,600 mounted dragoons ahead, and they reached the pass on April 12. The Mexican artillery prematurely fired on them and therefore revealed their positions, beginning the skirmish.

Instead of taking the main road, Scott's troops trekked through the rough terrain to the north, setting up his artillery on the high ground and quietly flanking the Mexicans. Although by then aware of the positions of U.S. troops, Santa Anna and his troops were unprepared for the onslaught that followed. In the battle fought on April 18, the Mexican army was routed. The U.S. Army suffered 400 casualties, while the Mexicans suffered over 1,000 casualties with 3,000 taken prisoner. In August 1847, Captain Kirby Smith, of Scott's 3rd Infantry, reflected on the resistance of the Mexican army:

They can do nothing and their continued defeats should convince them of it. They have lost six great battles we have captured six hundred and eight cannon, nearly one hundred thousand stands of arms, made twenty thousand prisoners, have the greatest portion of their country and are fast advancing on their Capital which must be ours,—yet they refuse to treat [i.e., negotiate terms]! [174]

The U.S. Army had expected a quick collapse of the forces of the Mexicans. Santa Anna, however, was determined to fight to the end, and Mexican soldiers continued to regroup after battles to fight yet again.

Pause at Puebla Edit

On May 1, 1847, Scott pushed on to Puebla, the second-largest city in Mexico. The city capitulated without resistance. The Mexican defeat at Cerro Gordo had demoralized Puebla's inhabitants, and they worried about harm to their city and inhabitants. It was standard practice in Western warfare for victorious soldiers to be let loose to inflict horrors on civilian populations if they resisted the threat of this was often used as a bargaining tool to secure surrender without a fight. Scott had orders which aimed to prevent his troops from such violence and atrocities. Puebla's ruling elite also sought to prevent violence, as did the Catholic Church, but Puebla's poor and working-class wanted to defend the city. U.S. Army troops who strayed outside at night were often killed. Enough Mexicans were willing to sell supplies to the U.S. Army to make local provisioning possible. [175] During the following months, Scott gathered supplies and reinforcements at Puebla and sent back units whose enlistments had expired. Scott also made strong efforts to keep his troops disciplined and treat the Mexican people under occupation justly, to keep good order and prevent any popular uprising against his army.

Advance on Mexico City and its capture Edit

With guerrillas harassing his line of communications back to Veracruz, Scott decided not to weaken his army to defend Puebla but, leaving only a garrison at Puebla to protect the sick and injured recovering there, advanced on Mexico City on August 7 with his remaining force. The capital was laid open in a series of battles around the right flank of the city defenses, the Battle of Contreras and Battle of Churubusco. After Churubusco, fighting halted for an armistice and peace negotiations, which broke down on September 6, 1847. With the subsequent battles of Molino del Rey and of Chapultepec, and the storming of the city gates, the capital was occupied. Scott became military governor of occupied Mexico City. His victories in this campaign made him an American national hero.

The Battle of Chapultepec in September 1847 was a siege on the castle of Chapultepec, built on a hill in Mexico City in the colonial era. At this time, this castle was a renowned military school in the capital. After the battle, which ended in a victory for the U.S., the legend of "Los Niños Héroes" was born. Although not confirmed by historians, six military cadets between the ages of 13 and 17 stayed in the school instead of evacuating. [176] They decided to stay and fight for Mexico. These Niños Héroes (boy heroes) became icons in Mexico's patriotic pantheon. Rather than surrender to the U.S. Army, some military cadets leaped from the castle walls. A cadet named Juan Escutia wrapped himself in the Mexican flag and jumped to his death. [176] [177] [178]

Santa Anna's last campaign Edit

In late September 1847, Santa Anna made one last attempt to defeat the U.S. Army, by cutting them off from the coast. General Joaquín Rea began the Siege of Puebla, soon joined by Santa Anna. Scott had left some 2,400 soldiers in Puebla, of whom around 400 were fit. After the fall of Mexico City, Santa Anna hoped to rally Puebla's civilian population against the U.S. soldiers under siege and subject to guerrilla attacks. Before the Mexican army could wipe out the Americans in Puebla, more troops landed in Veracruz under the command of Brigadier General Joseph Lane. At Puebla, they sacked the town. Santa Anna was not able to provision his troops, who effectively dissolved as a fighting force to forage for food. [179] Puebla was relieved by Lane on October 12, following his defeat of Santa Anna at the Battle of Huamantla on October 9. The battle was Santa Anna's last. Following the defeat, the new Mexican government led by Manuel de la Peña y Peña asked Santa Anna to turn over command of the army to General José Joaquín de Herrera. [ citation needed ]

Occupation of Mexico City Edit

Following the capture of the capital, the Mexican government moved to the temporary capital at Querétaro. In Mexico City, U.S. forces became an army of occupation and subject to stealth attacks from the urban population. Conventional warfare gave way to guerrilla warfare by Mexicans defending their homeland. They inflicted significant casualties on the U.S. Army, particularly on soldiers slow to keep up.

General Scott sent about a quarter of his strength to secure his line of communications to Veracruz from the Light Corps of General Rea and other Mexican guerrilla forces that had made stealth attacks since May. Mexican guerrillas often tortured and mutilated the bodies of the American troops, as revenge and warning. Americans interpreted these acts not as Mexicans' defense of their patria, but as evidence of Mexicans' brutality as racial inferiors. For their part, U.S. soldiers took revenge on Mexicans for the attacks, whether or not they were individually suspected of guerrilla acts.

Scott had planned to make total war on the Mexican population, but since he was losing soldiers to guerrilla attacks, he had to make some decisions. He viewed guerrilla attacks as contrary to the "laws of war" and threatened the property of populations that appeared to harbor the guerrillas. Captured guerrillas were to be shot, including helpless prisoners, with the reasoning that the Mexicans did the same. Historian Peter Guardino contends that the U.S. Army command was complicit in the attacks against Mexican civilians. By threatening the civilian populations' homes, property, and families with burning whole villages, looting, and raping women, the U.S. Army separated guerrillas from their base. "Guerrillas cost the Americans dearly, but indirectly cost Mexican civilians more." [180]

Scott strengthened the garrison of Puebla and by November had added a 1,200-man garrison at Jalapa, established 750-man posts along the main route between the port of Veracruz and the capital, at the pass between Mexico City and Puebla at Rio Frio, at Perote and San Juan on the road between Jalapa and Puebla, and at Puente Nacional between Jalapa and Veracruz. [181] He had also detailed an anti-guerrilla brigade under Lane to carry the war to the Light Corps and other guerrillas. He ordered that convoys would travel with at least 1,300-man escorts. Victories by Lane over the Light Corps at Atlixco (October 18, 1847), at Izúcar de Matamoros (November 23, 1847), and at Galaxara Pass (November 24, 1847) weakened General Rea's forces. [ citation needed ]

Later a raid against the guerrillas of Padre Jarauta at Zacualtipan (25 February 1848) further reduced guerrilla raids on the American line of communications. After the two governments concluded a truce to await ratification of the peace treaty, on March 6, 1848, formal hostilities ceased. However, some bands continued in defiance of the Mexican government until the U.S. Army's evacuation in August. [182] Some were suppressed by the Mexican Army or, like Padre Jarauta, executed. [183] [184]

Desertions Edit

Desertion was a major problem for both armies. In the Mexican Army, desertions depleted forces on the eve of battle. Most soldiers were peasants who had a loyalty to their village and family but not to the generals who had conscripted them. Often hungry and ill, underequipped, only partially trained, and under-paid, the soldiers were held in contempt by their officers and had little reason to fight the Americans. Looking for their opportunity, many slipped away from camp to find their way back to their home village. [185]

The desertion rate in the U.S. Army was 8.3% (9,200 out of 111,000), compared to 12.7% during the War of 1812 and usual peacetime rates of about 14.8% per year. [186] Many men deserted to join another U.S. unit and get a second enlistment bonus. Some deserted because of the miserable conditions in camp. It has been suggested that others used the army to get free transportation to California, where they deserted to join the gold rush [187] this, however, is unlikely as gold was only discovered in California on January 24, 1848, less than two weeks before the war concluded. By the time word reached the eastern U.S. that gold had been discovered, word also reached it that the war was over.

Hundreds of U.S. deserters went over to the Mexican side. Nearly all were recent immigrants from Europe with weak ties to the U.S. The Mexicans issued broadsides and leaflets enticing U.S. soldiers with promises of money, land bounties, and officers' commissions. Mexican guerrillas shadowed the U.S. Army and captured men who took unauthorized leave or fell out of the ranks. The guerrillas coerced these men to join the Mexican ranks. The generous promises proved illusory for most deserters, who risked execution if captured by U.S. forces. [ citation needed ]

San Patricios Edit

The most famous group of deserters from the U. S. Army, was the Saint Patrick's Battalion or (San Patricios), composed primarily of several hundred immigrant soldiers, the majority Catholic Irish and German immigrants, who deserted the U.S. Army because of ill-treatment or sympathetic leanings to fellow Mexican Catholics and joined the Mexican army. The battalion also included Canadians, English, French, Italians, Poles, Scots, Spaniards, Swiss, and Mexican people, many of whom were members of the Catholic Church. [188]

Most of the battalion were killed in the Battle of Churubusco about 100 were captured by the U.S., and roughly half of the San Patricios were tried and were hanged as deserters following their capture at Churubusco in August 1847. [187] The leader, John Riley, was branded. [189] A bust of John Riley and a plaque on the façade of a building in Plaza San Jacinto, San Angel commemorates the place where they were hanged. [190]

Outnumbered militarily and with many large cities of the Mexican heartland including its capital occupied, Mexico could not defend itself in conventional warfare. Mexico faced many continuing internal divisions between factions so that bringing the war to a formal end was not straightforward. There were also complications in the U.S. for negotiating the peace. Peace came in Alta California in January 1847 with the Treaty of Cahuenga, with the Californios (Mexican residents of Alta California) capitulating to the American forces. [191] A more comprehensive peace treaty was needed to end the conflict.

The U.S. forces had gone from being an army of conquest on the periphery for territory it desired to incorporate, to an invading force in central Mexico, potentially making it an army of long-term occupation. Mexico did not necessarily have to sign a peace treaty but could have continued with long-term guerrilla warfare against the U.S. Army. However, it could not expel the invaders, so negotiating a treaty became more necessary. [192] Polk's wish for a short war of conquest against a perceived weak enemy with no will to fight had turned into a long and bloody conflict in Mexico's heartland. Negotiating a treaty was in the best interest of the United States. It was not easy to achieve. Polk lost confidence in his negotiator Nicholas Trist and dismissed him as peace negotiations dragged on. Trist ignored the fact that he no longer had the authorization to act for the United States. When Trist managed to get yet another Mexican government to sign the Treaty of Guadalupe Hidalgo, Polk was presented with an accomplished fact and decided to take it to Congress for ratification. Ratification was fraught, since the Democrats had lost the elections of 1846, and Whigs opposed to the war were now in ascendance.

All-Mexico Movement Edit

Having won a decisive victory, the U.S. was divided on what the peace should entail. Now that the U.S. had gone far beyond the territorial gains it initially envisioned by invading central Mexico with its dense population, the question was raised whether to annex the entirety of Mexico. After the Wilmot Proviso, there was a lessening of fervor for the idea, but the taking of Mexico City had revived enthusiasm. [193] There were fierce objections in Congress to that on racial grounds. South Carolina Senator John C. Calhoun argued that absorbing Mexico would threaten U.S. institutions and the character of the country. "We have never dreamt of incorporating into our Union any but the Caucasian race—the free white race. To incorporate Mexico, would be the first instance of the kind, of incorporating an Indian race for more than half of the Mexicans are Indians, and the other is composed chiefly of mixed tribes. I protest against such a union as that! Ours, sir, is the Government of a white race. We are anxious to force free government on all and I see that it has been urged . that it is the mission of this country to spread civil and religious liberty over all the world, and especially over this continent. It is a great mistake."

Beyond the racial argument, Calhoun contended that the U.S. could not be both an empire and a republic, and he argued that being an empire would strengthen the central government and be detrimental to individual states. [194] Rhode Island Whig Senator John Clarke also objected to annexing all of Mexico. "To incorporate such a disjointed and degraded mass into even a limited participation with our social and political rights, would be fatally destructive to the institutions. of our country. There is a moral pestilence to such a people which is contagious – a leprosy that will destroy [us]." [195]

Treaty of Guadalupe Hidalgo Edit

The Treaty of Guadalupe Hidalgo, signed on February 2, 1848, by diplomat Nicholas Trist and Mexican plenipotentiary representatives Luis G. Cuevas, Bernardo Couto, and Miguel Atristain, ended the war. The treaty gave the U.S. undisputed control of Texas, established the U.S.-Mexican border along the Rio Grande, and ceded to the United States the present-day states of California, Nevada, and Utah, most of New Mexico, Arizona and Colorado, and parts of Texas, Oklahoma, Kansas, and Wyoming. In return, Mexico received $15 million [196] ($449 million today) – less than half the amount the U.S. had attempted to offer Mexico for the land before the opening of hostilities [197] – and the U.S. agreed to assume $3.25 million ($97 million today) in debts that the Mexican government owed to U.S. citizens. [198] The area of domain acquired was given by the Federal Interagency Committee as 338,680,960 acres. The cost was $16,295,149 or approximately 5 cents per acre. [199] The area amounted to one-third of Mexico's original territory from its 1821 independence.

The treaty was ratified by the U.S. Senate by a vote of 38 to 14 on March 10 and by Mexico through a legislative vote of 51–34 and a Senate vote of 33–4, on May 19. News that New Mexico's legislative assembly had passed an act for the organization of a U.S. territorial government helped ease Mexican concern about abandoning the people of New Mexico. [200] The acquisition was a source of controversy, especially among U.S. politicians who had opposed the war from the start. A leading anti-war U.S. newspaper, the Whig National Intelligencer, sardonically concluded that "We take nothing by conquest . Thank God." [10] [11]

The acquired lands west of the Rio Grande are traditionally called the Mexican Cession in the U.S., as opposed to the Texas Annexation two years earlier, though the division of New Mexico down the middle at the Rio Grande never had any basis either in control or Mexican boundaries. Mexico never recognized the independence of Texas [201] before the war and did not cede its claim to territory north of the Rio Grande or Gila River until this treaty.

Before ratifying the treaty, the U.S. Senate made two modifications: changing the wording of Article IX (which guaranteed Mexicans living in the purchased territories the right to become U.S. citizens) and striking out Article X (which conceded the legitimacy of land grants made by the Mexican government). On May 26, 1848, when the two countries exchanged ratifications of the treaty, they further agreed to a three-article protocol (known as the Protocol of Querétaro) to explain the amendments. The first article claimed that the original Article IX of the treaty, although replaced by Article III of the Treaty of Louisiana, would still confer the rights delineated in Article IX. The second article confirmed the legitimacy of land grants under Mexican law. [202] The protocol was signed in the city of Querétaro by A. H. Sevier, Nathan Clifford, and Luis de la Rosa. [202]

Article XI offered a potential benefit to Mexico, in that the U.S. pledged to suppress the Comanche and Apache raids that had ravaged the region and pay restitution to the victims of raids it could not prevent. [203] However, the Indian raids did not cease for several decades after the treaty, although a cholera epidemic in 1849 greatly reduced the numbers of the Comanche. [204] Robert Letcher, U.S. Minister to Mexico in 1850, was certain "that miserable 11th article" would lead to the financial ruin of the U.S. if it could not be released from its obligations. [205] The U.S. was released from all obligations of Article XI five years later by Article II of the Gadsden Purchase of 1853. [206]

Altered territories Edit

Before the secession of Texas, Mexico comprised almost 1,700,000 sq mi (4,400,000 km 2 ), but by 1849 it was just under 800,000 square miles (2,100,000 km 2 ). Another 30,000 square miles (78,000 km 2 ) were sold to the U.S. in the Gadsden Purchase of 1853, so the total reduction of Mexican territory was more than 55%, or 900,000 square miles (2,300,000 km 2 ). [207] Although the annexed territory was about the size of Western Europe, it was sparsely populated. The land contained about 14,000 non-indigenous people in Alta California [208] and about 60,000 in Nuevo México, [209] as well as large Indian nations, such as the Papago, Pima, Puebloan, Navajo, Apache and many others. Although some native people relocated farther south in Mexico, the great majority remained in the U.S. territory.

The U.S. settlers surging into the newly conquered Southwest were openly contemptuous of Mexican law (a civil law system based on the law of Spain) as alien and inferior and disposed of it by enacting reception statutes at the first available opportunity. However, they recognized the value of a few aspects of Mexican law and carried them over into their new legal systems. For example, most of the Southwestern states adopted community property marital property systems, as well as water law.

Mexicans and Indians in the annexed territories faced a loss of civil and political rights, even though the Treaty of Guadalupe Hidalgo promised U.S. citizenship to all Mexican citizens living in the territory of the Mexican Cession. The U.S. government withheld citizenship from Indians in the Southwest until the 1930s, although they were citizens under Mexican law. [210]

Impact on the United States Edit

In much of the United States, victory and the acquisition of new land brought a surge of patriotism. Victory seemed to fulfill Democrats' belief in their country's Manifest Destiny. Although the Whigs had opposed the war, they made Zachary Taylor their presidential candidate in the election of 1848, praising his military performance while muting their criticism of the war.

Has the Mexican War terminated yet, and how? Are we beaten? Do you know of any nation about to besiege South Hadley [Massachusetts]? If so, do inform me of it, for I would be glad of a chance to escape, if we are to be stormed. I suppose [our teacher] Miss [Mary] Lyon [founder of Mount Holyoke College] would furnish us all with daggers and order us to fight for our lives .

A month before the end of the war, Polk was criticized in a United States House of Representatives amendment to a bill praising Taylor for "a war unnecessarily and unconstitutionally begun by the President of the United States." This criticism, in which Congressman Abraham Lincoln played an important role with his Spot Resolutions, followed congressional scrutiny of the war's beginnings, including factual challenges to claims made by President Polk. [212] [213] The vote followed party lines, with all Whigs supporting the amendment. Lincoln's attack won lukewarm support from fellow Whigs in Illinois but was harshly counter-attacked by Democrats, who rallied pro-war sentiments in Illinois Lincoln's Spot Resolutions haunted his future campaigns in the heavily Democratic state of Illinois and were cited by his rivals well into his presidency. [214]

While Whig Ralph Waldo Emerson rejected war "as a means of achieving America's destiny," toward the end of the war he wrote: "The United States will conquer Mexico, but it will be as the man swallows the arsenic, which brings him down in turn. Mexico will poison us." [215] He later accepted that "most of the great results of history are brought about by discreditable means." [216]

Veterans of the war were often broken men. "As the sick and wounded from Taylor's and Scott's campaigns made their way back from Mexico to the United States, their condition shocked the folks at home. Husbands, sons, and brothers returned in broken health, some with missing limbs." [217] The 1880 "Republican Campaign Textbook" by the Republican Congressional Committee [218] describes the war as "Feculent, reeking Corruption" and "one of the darkest scenes in our history—a war forced upon our and the Mexican people by the high-handed usurpations of Pres't Polk in pursuit of territorial aggrandizement of the slave oligarchy."

Following the signing of the 1848 treaty, Polk sought to send troops to Yucatan, where there was a civil war between secessionists and those supporting the Mexican government. The U.S. Congress refused his request. The Mexican War was supposed to be short and nearly bloodless. It was neither. Congress did not support more foreign conflict. [219]

Effect on the American military in the Civil War Edit

Many of the military leaders on both sides of the American Civil War of 1861–1865 had trained at the U.S. Military Academy at West Point and had fought as junior officers in Mexico. This list includes military men fighting for the Union: Ulysses S. Grant, George B. McClellan, William T. Sherman, George Meade, and Ambrose Burnside. Military men who joined the Southern secessionists of the Confederacy included Robert E. Lee, Stonewall Jackson, James Longstreet, Joseph E. Johnston, Braxton Bragg, Sterling Price, and the future Confederate President Jefferson Davis. Both sides had leaders with significant experience in active combat, strategy, and tactics.

For Grant, who went on to lead Union forces in the Civil War and later was elected president, "it also tutored him in the manifold ways wars are shot through with political calculations." [220] Grant had served in Mexico under General Zachary Taylor and was appointed acting assistant quartermaster for Taylor's army, a post he tried to decline since it took him away from the battlefield. However, "The appointment was actually a godsend for Grant, turning him into a complete soldier, adept at every facet of army life, especially logistics. This provided invaluable training for the Civil War when Grant would need to sustain gigantic armies in the field, distant from northern supply depots." [221] Grant saw considerable combat and demonstrated his coolness under fire. In the Battle of Chapultepec, he and his men hoisted a howitzer into a church belfry that had a commanding view of the San Cosme gate. The action brought him the honorary rank of brevet captain, for "gallant and meritorious conduct in the battle of Chapultepec." [222]

Grant later recalled in his Memoirs, published in 1885, that "Generally, the officers of the army were indifferent whether the annexation [of Texas] was consummated or not but not so all of them. For myself, I was bitterly opposed to the measure, and to this day regard the war, which resulted, as one of the most unjust ever waged by a stronger against a weaker nation. It was an instance of a republic following the bad example of European monarchies, in not considering justice in their desire to acquire additional territory." [223] Grant also expressed the view that the war against Mexico had brought punishment on the United States in the form of the American Civil War. "The Southern rebellion was largely the outgrowth of the Mexican war. Nations, like individuals, are punished for their transgressions. We got our punishment in the most sanguinary and expensive war of modern times." [224]

Robert E. Lee, commander of the Confederate forces through the end of the Civil War, began building his reputation as a military officer in America's war against Mexico. At the start of the Mexican–American War, Captain Lee invaded Mexico with General Wool's engineering department from the North. By early 1847, he helped take the Mexican cities of Vera Cruz, Cerro Gordo, Contreras, Churubusco, Molino del Rey, and Chapultepec. Lee was wounded in Chapultepec. General Scott described Robert E. Lee as "gallant and indefatigable", saying that Lee had displayed the "greatest feat of physical and moral courage performed by any individual in [his] knowledge during the campaign". [225] Grant gained insight into Robert E. Lee, as his memoir states, "I had known him personally, and knew that he was mortal and it was just as well that I felt this." [226]

In 1861, General Scott advised Abraham Lincoln to ask Lee to command U.S. forces. Lee declined and later recounted "I declined the offer he made me to take command of the army that was brought into the field, stating candidly and as courteously as I could that though opposed to secession and deprecating war, I could take no part in the invasion of the southern states." [227]

Social and political context Edit

Despite initial objections from the Whigs and from abolitionists, the Mexican war nevertheless united the U.S. in a common cause and was fought almost entirely by volunteers. The United States Army swelled from just over 6,000 to more than 115,000. The majority of 12-month volunteers in Scott's army decided that a year's fighting was enough and returned to the U.S. [228]

Anti-slavery elements fought for the exclusion of slavery from any territory absorbed by the U.S. [229] In 1847, the House of Representatives passed the Wilmot Proviso, stipulating that none of the territory acquired should be open to slavery. If successful, the Wilmot Proviso would have effectively cancelled out the 1820 Missouri Compromise, since it would have prohibited slavery in an area below the parallel 36°30′ north. The Senate avoided the issue, and a late attempt to add it to the Treaty of Guadalupe Hidalgo was defeated because Southern Senators had the votes to prevent its addition. The House of Representatives is apportioned by population, and the North's was growing, allowing it to win the majority of the House in the 1846 elections but the Senate representation is two per state and Southerners had enough votes to block the addition.

The war proved a decisive event for the U.S., marking a significant turning point for the nation as a growing military power. It is also a milestone in the U.S. narrative of Manifest Destiny. The war did not resolve the issue of slavery in the U.S. but rather in many ways inflamed it, as potential westward expansion of the institution became an increasingly central and heated theme in national debates preceding the American Civil War. [230] [ need quotation to verify ] By extending the territory of the United States to the Pacific Ocean, the end of the Mexican–American War marked a new step in the huge migrations of Americans to the West, which culminated in transcontinental railroads and the Indian wars later in the same century. [231] [ need quotation to verify ]

Veterans of the war Edit

Following the Civil War, veterans of the Mexican war began to organize themselves as veterans regardless of rank and lobbied for their service. [232] Initially they sought to create a soldiers' home for aged and ailing veterans, but then began pushing for pensions in 1874. There was resistance in Congress since veterans had received warrants for up to 160 acres of land for their service pensions would have put a fiscal strain on the government. [233] The politics were complicated since so many veterans of the Mexican war fought for the Confederacy in the Civil War. Republican Congressmen accused them of attempting to give federal aid to former Confederates. This led to a thirteen-year Congressional debate over the loyalty of the veterans and their worthiness to receive federal assistance in their declining years. [234]

In 1887, the Mexican Veteran Pension Law went into effect, making veterans eligible for a pension for their service. Surviving officers and enlisted men were placed on a pension roll, which included volunteers, militias, and marines who had served at least 60 days and were at least 62 years old. Widows of veterans who had not remarried were eligible for their late husband's pension. Excluded were "any person while under the political disabilities imposed by the Fourteenth Amendment to the United States Constitution", that is, veterans who had fought for the Confederacy in the Civil War. [235]

Effects on Mexico Edit

For Mexico, the war had remained a painful historical event for the country, losing territory and highlighting the domestic political conflicts that were to continue for another 20 years. The Reform War between liberals and conservatives was followed by the invasion of the French, who set up the puppet monarchy. The war caused Mexico to enter "a period of self-examination . as its leaders sought to identify and address the reasons that had led to such a debacle." [236] In the immediate aftermath of the war, a group of Mexican writers including Ignacio Ramírez, Guillermo Prieto, José María Iglesias, and Francisco Urquidi compiled an assessment of the reasons for the war and Mexico's defeat, edited by Mexican army officer Ramón Alcaraz. They wrote that for "the true origin of the war, it is sufficient to say that the insatiable ambition of the United States, favored by our weakness, caused it." [12] The work was translated to English by Colonel Albert Ramsey, a veteran of the Mexican–American War, and published in 1850. [237]

Despite his being vilified and scapegoated for Mexico's loss in the war, Santa Anna returned to power for one last term as president. After he sold the Mesilla Valley in 1853 to the U.S., (the Gadsden Purchase) that allowed construction of a transcontinental railway on a better route, he was ousted and went into a lengthy exile. In exile he drafted his version of events, which were not published until much later.

Mexico Edit

Once the French were expelled in 1867 and the liberal republic re-established, Mexico began reckoning with the legacy of the war. The story of the Niños Héroes became the narrative that helped Mexicans to come to terms with the war. Boy cadets sacrificing themselves for the patria as martyrs in the Battle of Chapultepec was inspiring, but their sacrifice was not commemorated until 1881 when surviving cadets formed an organization to support the Military Academy of Mexico. One of the cadets taken prisoner designed the monument, a small cenotaph was erected at the base of Chapultepec hill on which the castle is built.


The message came in the form of a coded telegram dispatched by Arthur Zimmermann, a Staatssekretär (a top-level civil servant) in the Foreign Office of the German Empire on January 17, 1917. The message was sent to the German ambassador to Mexico, Heinrich von Eckardt. [4] Zimmermann sent the telegram in anticipation of the resumption of unrestricted submarine warfare by Germany on February 1, which the German government presumed would almost certainly lead to war with the United States. The telegram instructed Eckardt that if the United States appeared certain to enter the war, he was to approach the Mexican government with a proposal for military alliance with funding from Germany. The decoded telegram was follows:

We intend to begin on the first of February unrestricted submarine warfare. We shall endeavor in spite of this to keep the United States of America neutral. In the event of this not succeeding, we make Mexico a proposal of alliance on the following basis: make war together, make peace together, generous financial support and an understanding on our part that Mexico is to reconquer the lost territory in Texas, New Mexico, and Arizona. The settlement in detail is left to you. You will inform the President of the above most secretly as soon as the outbreak of war with the United States of America is certain, and add the suggestion that he should, on his own initiative, invite Japan to immediate adherence and at the same time mediate between Japan and ourselves. Please call the President's attention to the fact that the ruthless employment of our submarines now offers the prospect of compelling England in a few months to make peace.

Previous German efforts to promote war Edit

Germany had long sought to incite a war between Mexico and the United States, which would have tied down American forces and slowed the export of American arms to the Allies. [5] The Germans had aided in arming Mexico, as shown by the 1914 Ypiranga Incident. [6] German Naval Intelligence officer Franz von Rintelen had attempted to incite a war between Mexico and the United States in 1915, giving Victoriano Huerta $12 million for that purpose. [7] The German saboteur Lothar Witzke, responsible for the March 1917 munitions explosion at the Mare Island Naval Shipyard in the San Francisco Bay Area, [8] and possibly responsible for the July 1916 Black Tom explosion in New Jersey, was based in Mexico City. The failure of United States troops to capture Pancho Villa in 1916 and the movement of President Carranza in favor of Germany emboldened the Germans to send the Zimmermann note. [9]

The German provocations were partially successful. President Woodrow Wilson ordered the military invasion of Veracruz in 1914 in the context of the Ypiranga Incident and against the advice of the British government. [10] War was prevented thanks to the Niagara Falls peace conference organized by the ABC nations, but the occupation was a decisive factor in Mexican neutrality in World War I. [11] Mexico refused to participate in the embargo against Germany and granted full guarantees to the German companies for keeping their operations open, specifically in Mexico City. [12] These guarantees lasted for 25 years coincidentally, it was on May 22, 1942 that Mexico declared war on the Axis Powers after the loss of two Mexican-flagged tankers that month to Kriegsmarine U-boats.

German motivations Edit

The Zimmermann Telegram was part of an effort carried out by the Germans to postpone the transportation of supplies and other war materials from the United States to the Allies, which were at war against Germany. [13] The main purpose of the telegram was to make the Mexican government declare war on the United States in hopes of tying down American forces and slowing the export of American arms. [14] The German High Command believed that it could defeat the British and French on the Western Front and strangle Britain with unrestricted submarine warfare before American forces could be trained and shipped to Europe in sufficient numbers to aid the Allies. The Germans were encouraged by their successes on the Eastern Front to believe that they could divert large numbers of troops to the Western Front in support of their goals. The Mexicans were willing to consider the alliance but declined the deal after Americans had been informed of the telegram.

Mexican President Venustiano Carranza assigned a military commission to assess the feasibility of the Mexican takeover of their former territories contemplated by Germany. [15] The generals concluded that it would not be possible or even desirable to attempt such an enterprise for the following reasons:

  • Mexico was in the midst of a civil war, and Carranza's position was far from secure. A declaration of war by his regime would have provided an opportunity for the opposing factions to align with the United States and Allies in exchange for diplomatic recognition.
  • The United States was far stronger militarily than Mexico was. Even if Mexico's military forces had been completely united and loyal to a single regime, no serious scenario existed under which it could have invaded and won a war against the United States.
  • The German government's promises of "generous financial support" were very unreliable. It had already informed Carranza in June 1916 that it could not provide the necessary gold needed to stock a completely-independent Mexican national bank. [16] Even if Mexico received financial support, it would still need to purchase arms, ammunition, and other needed war supplies from the ABC nations (Argentina, Brazil, and Chile), which would strain relations with them, as explained below.
  • Even if by some chance Mexico had the military means to win a conflict against the United States and to reclaim the territories in question, it would have had severe difficulty conquering and pacifying a large English-speaking population which had long self-government and was better supplied with arms than were most other civilian populations.
  • Other foreign relations were at stake. The ABC nations had organized the Niagara Falls peace conference in 1914 to avoid a full-scale war between the United States and Mexico over the United States occupation of Veracruz. Mexico entering a war against the United States would strain relations with those nations.

The Carranza government was recognized de jure by the United States on August 31, 1917 as a direct consequence of the Zimmermann Telegram to ensure Mexican neutrality during World War I. [17] [18] After the military invasion of Veracruz in 1914, Mexico did not participate in any military excursion with the United States in World War I. [11] That ensured that Mexican neutrality was the best outcome that the United States could hope for even if it allowed German companies to keep their operations in Mexico open. [12]

Zimmermann's office sent the telegram to the German embassy in the United States for retransmission to Eckardt in Mexico. It has traditionally been claimed that the telegram was sent over three routes and was transmitted by radio and also sent over two trans-atlantic telegraph cables operated by neutral governments (the United States and Sweden) for the use of their diplomatic services. However, it has been established that two methods were used. The Germans delivered the message to the United States embassy in Berlin, and it then passed by diplomatic cable first to Copenhagen and then to London for onward transmission over transatlantic cable to Washington. [19]

Direct telegraph transmission of the telegram was impossible because the British had cut the German international cables at the outbreak of war. However, Germany could communicate wirelessly through the Telefunken plant, operating under Atlantic Communication Company in West Sayville, New York, where the telegram was relayed to the Mexican Consulate. Ironically, the station was under the control of the US Navy, which operated it for Atlantic Communication Company, the American subsidiary of the German entity.

Also, the United States allowed limited use of its diplomatic cables with Germany to communicate with its ambassador in Washington. The facility was supposed to be used for cables connected with Wilson's peace proposals. [19]

The Swedish cable ran from Sweden, and the American cable from the American embassy in Denmark. However, neither cable ran directly to the United States. Both cables passed through a relay station at Porthcurno, near Land's End, the westernmost tip of England, where the signals were boosted for the long transoceanic jump. All traffic through the Porthcurno relay was copied to British intelligence, particularly to the codebreakers and analysts in Room 40 at the Admiralty. [20]

After the Germans' telegraph cables had been cut, the German Foreign Office appealed to the United States for use of their cable for diplomatic messages. President Wilson agreed in the belief both that such co-operation would sustain continued good relations with Germany and that more efficient German-American diplomacy could assist Wilson's goal of a negotiated end to the war. The Germans handed in messages to the American embassy in Berlin, which were relayed to the embassy in Denmark and then to the United States by American telegraph operators. The United States placed conditions on German usage, most notably that all messages had to be in cleartext (uncoded). However, Wilson later reversed the order and relaxed the wireless rules to allow coded messages to be sent. [21] The Germans assumed that the cable was secure and so used it extensively. [20]

However, that put German diplomats in a precarious situation since they relied on the United States to transmit Zimmermann's note to its final destination, but the message's unencrypted contents would be deeply alarming to the Americans. The Germans persuaded US Ambassador James W. Gerard to accept it in coded form, and it was transmitted on January 16, 1917. [20]

In Room 40, Nigel de Grey had partially decoded the telegram by the next day. [19] By 1917, the diplomatic code 13040 had been in use for many years. Since there had been ample time for Room 40 to reconstruct the code cryptanalytically, it was readable to a fair degree. Room 40 had obtained German cryptographic documents, including the diplomatic code 3512 (captured during the Mesopotamian campaign), which was a later updated code that was similar to but not really related to code 13040, and naval code SKM (Signalbuch der Kaiserlichen Marine), ⁠which was useless for decoding the Zimmermann Telegram but valuable to decode naval traffic, which had been retrieved from the wrecked cruiser SMS Magdeburg by the Russians, who passed it to the British. [22]

Disclosure of the telegram would sway American public opinion against Germany if the British could convince the Americans that the text was genuine, but the Room 40 chief William Reginald Hall was reluctant to let it out because the disclosure would expose the German codes broken in Room 40 and British eavesdropping on the US cable. Hall waited three weeks during which de Grey and cryptographer William Montgomery completed the decryption. On February 1, Germany announced resumption of "unrestricted" submarine warfare, an act that led the United States to break off diplomatic relations with Germany on February 3. [20]

Hall passed the telegram to the British Foreign Office on February 5 but still warned against releasing it. Meanwhile, the British discussed possible cover stories to explain to the Americans how they obtained the coded text of the telegram without admitting to their ability to intercept American diplomatic communications, which they would continue to do for another 25 years, and to explain how they obtained the cleartext of the telegram without letting the Germans know that the codes had been broken. Furthermore, the British needed to find a way to convince the Americans the message was not a forgery. [2]

For the first story, the British obtained the coded text of the telegram from the Mexican commercial telegraph office. The British knew that since the German embassy in Washington would relay the message by commercial telegraph, the Mexican telegraph office would have the coded text. "Mr. H", a British agent in Mexico, bribed an employee of the commercial telegraph company for a copy of the message. Sir Thomas Hohler, the British ambassador in Mexico, later claimed to have been "Mr. H" or at least to have been involved with the interception in his autobiography. [23] [ citation needed ] The coded text could then be shown to the Americans without embarrassment.

Moreover, the retransmission was encoded with the older code 13040 and so by mid-February, the British had the complete text and the ability to release the telegram without revealing the extent to which the latest German codes had been broken. (At worst, the Germans might have realized that the 13040 code had been compromised, but that was a risk worth taking against the possibility of United States entry into the war.) Finally, since copies of the 13040 codetext would also have been deposited in the records of the American commercial telegraph company, the British had the ability to prove the authenticity of the message to the American government. [3]

As a cover story, the British could publicly claim that their agents had stolen the telegram's decoded text in Mexico. Privately, the British needed to give the Americans the 13040 code so that the American government could verify the authenticity of the message independently with their own commercial telegraphic records, but the Americans agreed to back the official cover story. The German Foreign Office refused to consider that their codes could have been broken but sent Eckardt on a witch hunt for a traitor in the embassy in Mexico. Eckardt indignantly rejected those accusations, and the Foreign Office eventually declared the embassy exonerated. [20]

Use Edit

On February 19, Hall showed the telegram to Edward Bell, the secretary of the American Embassy in Britain. Bell was at first incredulous and thought that it was a forgery. Once Bell was convinced the message was genuine, he became enraged. On February 20, Hall informally sent a copy to US Ambassador Walter Hines Page. On February 23, Page met with British Foreign Minister Arthur Balfour and was given the codetext, the message in German, and the English translation. The British had obtained a further copy in Mexico City, and Balfour could obscure the real source with the half-truth that it had been "bought in Mexico". [24] Page then reported the story to Wilson on February 24, 1917, including details to be verified from telegraph-company files in the United States. Wilson felt "much indignation" toward the Germans and wanted to publish the Zimmermann Telegraph immediately after he had received it from the British, but he delayed until March 1, 1917. [25]

Many Americans then held anti-Mexican as well as anti-German views, Mexicans had a considerable amount of anti-American sentiment in return, some of which was caused by the American occupation of Veracruz. [26] General John J. Pershing had long been chasing the revolutionary Pancho Villa for raiding into American territory and carried out several cross-border expeditions. News of the telegram further inflamed tensions between the United States and Mexico.

However, many Americans, particularly those with German or Irish ancestry, wished to avoid the conflict in Europe. Since the public had been told falsely that the telegram had been stolen in a decoded form in Mexico, the message was at first widely believed to be an elaborate forgery created by British intelligence. That belief, which was not restricted to pacifist and pro-German lobbies, was promoted by German and Mexican diplomats alongside some antiwar American newspapers, especially those by the Hearst press empire.

The Wilson administration was thus presented with a dilemma. With the evidence the United States had been provided confidentially by the British, Wilson realized the message was genuine, but he could not make the evidence public without compromising the British codebreaking operation.

Any doubts as to the authenticity of the telegram were removed by Zimmermann himself. At a press conference on March 3, 1917, he told an American journalist, "I cannot deny it. It is true." Then, on March 29, 1917, Zimmermann gave a speech in the Reichstag in which he admitted that the telegram was genuine. [27] Zimmermann hoped that Americans would understand that the idea was that Germany would not fund Mexico's war with the United States unless the Americans joined World War I.

On February 1, 1917, Germany began unrestricted submarine warfare against all ships in the Atlantic bearing the American flag, both passenger and merchant ships. Two ships were sunk in February, and most American shipping companies held their ships in port. Besides the highly-provocative war proposal to Mexico, the telegram also mentioned "ruthless employment of our submarines". Public opinion demanded action. Wilson had refused to assign US Navy crews and guns to the merchant ships, but once the Zimmermann note was public, Wilson called for arming the merchant ships although antiwar members of the US Senate blocked his proposal. [28]

On April 6, 1917, Congress voted to declare war on Germany. Wilson had asked Congress for "a war to end all wars" that would "make the world safe for democracy". [29]

Wilson considered another military invasion of Veracruz and Tampico in 1917–1918, [30] [31] to pacify the Isthmus of Tehuantepec and Tampico oil fields and to ensure their continued production during the civil war, [31] [32] but this time, Mexican President Venustiano Carranza, recently installed, threatened to destroy the oil fields if the US Marines landed there. [33] [34]

The Japanese government, another nation mentioned in the Zimmerman Telegram, was already involved in World War I, on the side of the Allies against Germany. The government later released a statement that Japan was not interested in changing sides and in attacking America. [35]

In October 2005, it was reported that an original typescript of the decoded Zimmermann Telegram had recently been discovered by an unnamed historian who was researching and preparing an official history of the United Kingdom's Government Communications Headquarters (GCHQ). The document is believed to be the actual telegram shown to the American ambassador in London in 1917. Marked in Admiral Hall's handwriting at the top of the document are the words: "This is the one handed to Dr Page and exposed by the President." Since many of the secret documents in this incident had been destroyed, it had previously been assumed that the original typed "decrypt" was gone forever. However, after the discovery of this document, the GCHQ official historian said: "I believe that this is indeed the same document that Balfour handed to Page." [36]

Mexico Almost Invaded the U.S. in 1917

What if Mexico had declared war on the United States?

It was one hundred years ago when Mexico almost invaded the United States.

In January 1917, German foreign secretary Arthur Zimmermann dispatched a coded telegram to Heinrich von Eckardt, the German ambassador to Mexico. With Germany locked in bloody stalemate with the Allies in France, and Britain’s naval blockade strangling the German economy, Kaiser Wilhelm’s government was about to make a fateful decision: declare unrestricted submarine warfare, which would allow U-boats to sink merchant ships on sight.

That also meant sinking the ships of neutral powers, most especially the United States, which would likely respond by declaring war on Germany. But Zimmermann had instructions for his ambassador: “We make Mexico a proposal of alliance on the following basis: make war together, make peace together, generous financial support and an understanding on our part that Mexico is to reconquer the lost territory in Texas, New Mexico, and Arizona.”

This was the famous Zimmermann Telegram. Decoded by the British, who passed it on to the Americans, it became a justification—along with unrestricted submarine warfare—for the U.S. declaration of war on Germany in April 1917.

In the end, Mexico turned down the proposal. But what if Mexico had declared war on the United States?

In fact, Mexican president Venustiano Carranza did order his government to study the German offer, according to Friedrich Katz, in his book The Secret War in Mexico. Carranza’s decision wasn’t surprising. In Mexican eyes, the United States had illegally seized one-third of Mexico’s territory during the 1847 Mexican-American War, including what are now the states of California, Utah, Nevada, Arizona and New Mexico. In 1916, a U.S. Army expeditionary force had entered Mexico in pursuit of the notorious revolutionary Pancho Villa, who had raided American territory.

However, when Mexican officials studied the proposal, they concluded that Germany would never be able to ship sufficient munitions (especially given the inevitable American blockade), and that annexing three U.S. states would lead to permanent conflict with America. Ironically, given the current furor over Mexican illegal immigrants in the United States, the Mexican government worried in 1917 that adding millions of Americans to Mexico’s population would mean that Mexicans couldn’t be sure “whether we had annexed them or they had annexed us.”

As Katz, an Austrian refugee from Hitler who became one of Mexico’s most important historians, put it: “All these reports show that Carranza did not want to rush into war with the United States, and certainly not on the basis of a German offer of Texas, Arizona and New Mexico. But it can also be surmised from these indications that he wanted to keep Germany in reserve for the eventuality, which Carranza considered a probable one, of an American attack on the Mexican oil fields.”

So what if Carranza had decided to ally with Germany and attack the United States, either to recover lost territory or to preempt a feared American seizure of Mexican oil? In 1917, the Mexican army numbered perhaps sixty-five thousand to one hundred thousand soldiers. In 1914, the U.S. Army had just ninety-eight thousand men. By the end of 1918, it had swelled to four million, of which two million had been sent to France. America also had tanks and aircraft (provided by the British and French while American industry geared up for war), a huge navy and plenty of money.

Short of Kaiser Wilhelm’s spike-helmeted legions storming New York and Baltimore, there was no way Mexico could seized the southwestern United States. Yet this didn’t matter to Germany. What Mexico could do was tie down American troops and equipment that otherwise would have been sent to Europe. Not that many U.S. troops would have been needed to stop a Mexican invasion, though recent history warns that many, many troops would have been needed to occupy Mexico. But a second Mexican-American war could easily have triggered a disproportionate response, as the American public demanded that the troops stay home and defend the nation.

And that’s where history might have changed. The focal point of global events in 1918 was France and Belgium, not Mexico or Texas. Russia, gripped by Bolshevik revolution, had pulled out of the war by 1918, leaving Germany free to transfer fifty divisions from the Eastern to the Western Front. In spring 1918, the Germans launched a massive offensive in France that nearly won the war.

What helped revive the exhausted British and French armies were the divisions of fresh Yank troops streaming off the transport ships and into the trenches. If those troops had stayed in America, it is possible that World War I might have ended later than it did, or perhaps even in a compromise peace instead of a German defeat.

Fortunately, none of this happened. In the end, the Zimmermann Telegram did accomplish something: it hastened Germany’s downfall.

Michael Peck is a contributing writer for the National Interest. He can be found on Twitter and Facebook.

Image: Lewis machine gun tests. Wikimedia Commons/Public domain

U.S.-Mexico Relations

After Mexican independence in 1810, Mexico and the United States had numerous territorial disputes. Political upheaval in Mexico and economic opportunity across the border spurred migration to the United States after the Mexican Revolution. The North American Free Trade Agreement (NAFTA) paved the way for a closer U.S.-Mexico relationship on security, trade, and counternarcotics.

In 1810, Father Miguel Hidalgo y Costilla calls for Mexican independence from Spain, spurring a series of revolts across the country that becomes known as the Hidalgo rebellion. The rebellion fails, but fighting continues. Meanwhile, the United States and Spain are locked in debate over the border between their territories. In 1819, the Adams-Onis Treaty, also known as the Transcontinental Treaty, draws a definitive border between Spanish land and the Louisiana Territory. The United States cedes California, New Mexico, Texas, and modern Arizona, Nevada, and Utah to Spain it also agrees to pay U.S. citizens' land claims against Spain up to $5 million.

In 1821, Mexico gains independence under the Treaty of Cordoba. The country is set up as a limited monarchy the Roman Catholic Church is the official state church and upper-class status is granted to the Spanish and mestizo populations.

Migration is the root of the first dispute between the United States and Mexico. In 1830, Mexico prohibits immigration to Texas from the United States in an effort to stem the influx of English-speaking settlers. Mexican President Antonio Lopez de Santa Anna tries to enforce the law by abolishing slavery and enforcing customs duties. In March 1836, Santa Anna is taken prisoner and signs a treaty recognizing the independence of Texas. In 1845, Texas becomes part of the United States as a slave state. Mexico then breaks diplomatic relations with the United States.

In 1845, U.S. President James Polk offers to purchase California and New Mexico from the Mexican government and seeks to make the Rio Grande River the border between the two countries, which would make Texas part of the United States. Advocates of "Manifest Destiny," the nineteenth-century concept that the United States had a moral obligation to expand to the Pacific coast, support the plan. Mexico refuses Polk's offer, and Polk sends military forces to the Rio Grande in retaliation. Fighting ensues a full-scale U.S. invasion follows.

In 1848, after the seizure of Mexico City, the Treaty of Guadalupe Hidalgo is signed, ending the Mexican-American War. The treaty obligates Mexico to cede present-day Arizona, California, and New Mexico, and parts of Colorado and Nevada. In return, the United States pays $15 million in compensation for war-related damage to Mexican land. The treaty also provides for the protection of the property and civil rights of the roughly eighty thousand Mexican nationals living in U.S. territory. Many become U.S. citizens, but most lose their land by force or fraud. The California gold rush prompts gold seekers to push out Mexican landowners.

In 1853, U.S. President Franklin Pierce purchases thirty thousand square miles of land along the Mesilla Valley, which runs from California to El Paso, for $10 million. He plans to use the land for a railroad to the Pacific Ocean. The Gadsden Purchase, as it becomes known, also resolves an outstanding border dispute between Mexico and the United States, and marks the last adjustment to the border between the two countries.

A joint British-French-Spanish force invades Mexico in 1862 in an attempt to collect on debts the Mexican government owes them. The British and Spanish armies vacate after reaching agreements with the government, but Napoleon III of France sends troops to Mexico City, where they force the president to flee. Meanwhile, a civil war rages on in the United States. France has significant interest in halting U.S. growth, and believes if it conquers Mexico, it may be able to aid the Confederates in dividing the United States into two countries. After sustained pressure from Washington, France pulls out its troops in 1867.

Labor shortages in the United States lead railway companies to recruit Mexicans after the Chinese Exclusion Act of 1882 halts immigration from China. Meanwhile, inspection stations are set up at ports of entry along the southern border. In 1904, the first U.S. border patrol is established to stop Asian workers from circumventing border controls and entering through Mexico. Historians estimate that over sixteen thousand Mexicans were working on the railroads by the early 1900s, representing as much as 60 percent of America's railway labor force at the time.

Unrest among peasants and urban workers triggers the Mexican Revolution. Political turmoil grows, with Emiliano Zapata leading in the south and Francisco "Pancho" Villa in the north. In 1911, dictator Porfirio Diaz, who famously said, "Poor Mexico, so far from God and so close to the United States," is overthrown. Mexican President Francisco Madero assumes power. The continued upheaval sends a flood of Mexican immigrants who are seeking refuge to the United States. More than 890,000 Mexicans migrate to the United States between 1910 and 1920, although some of them ultimately return.

In 1913, Mexican President Madero is killed in a coup led by General Victoriano Huerta. In April 1914, nine U.S. soldiers are arrested and detained by Heurta's army for allegedly entering a prohibited zone in Tampico. Mexico apologizes, but U.S. President Woodrow Wilson sends Marines to the port of Veracruz to "obtain from General Huerta and his adherents the fullest recognition of the rights and dignity of the United States." The invasion inflames anti-American sentiment in Mexico, and Huerta flees the capital soon afterward due to ongoing political upheaval.

In May 1916, Francisco "Pancho" Villa, who attained notoriety as a general during the Mexican Revolution, leads hundreds of Mexicans in an attack on the U.S. town of Columbus, New Mexico, killing seventeen Americans and burning the town center. The incursion marks the first attack on U.S. territory since 1812. The American public is outraged, and U.S. President Wilson sends ten thousand troops into Mexico in pursuit of Villa. One year later, they withdraw, having failed to apprehend the guerilla leader. The prolonged U.S. military presence further damages U.S.-Mexico relations.

In 1917, Mexico adopts a new constitution to ensure permanent democracy. In 1929, the National Revolutionary Party is formed it is later renamed the Institutional Revolutionary Party (Partido Revolucionario Institucional), or PRI. The party leads Mexico for the next seventy-one years.

With World War I raging in Europe and the United States remaining neutral, a secret telegram from German’s foreign minister to his Mexican counterpart offers to restore territories lost by Mexico in the 1846 war if Mexico attacks the United States. Germany hopes such a war will distract the U.S. military, which it fears will soon enter into the European conflict. The telegram is intercepted and published in the United States, leading to an outcry and a declaration of war against Germany.

The U.S. Congress passes the Emergency Quota Act of 1921, restricting the flow of Southern and Eastern Europeans into the country. Mexicans are excluded from quota requirements. The subsequent Immigration Act of 1924 extends the restrictions to East Asians and South Asians. Though Mexican immigration remains unrestricted, the act establishes border stations to formally admit Mexican workers and to collect visa fees and taxes from those entering. That same year, the U.S. Border Patrol is created, though in its early years, the patrol is primarily focused on the Canadian border. By 1930, the U.S. census counts six hundred thousand Mexican immigrants residing in the United States, up from two hundred thousand in 1910. Mexicans still comprise less than 5 percent of the immigrant workforce, not including undocumented immigrants who slip across the porous border.

During the Great Depression, tens of thousands of Midwestern farmers in the United States migrate to California in search of work. Americans begin to view Mexicans as competitors for jobs as well as a drain on social services. This prompts a forced repatriation program of Mexicans and Mexican-Americans, while hundreds of thousands more, wary of the changed climate, return to Mexico voluntarily.

In 1933, U.S. President Franklin Roosevelt takes office and sets out to improve relations with Latin America. In his inaugural speech, he says "I would dedicate this nation to the policy of the good neighbor—the neighbor who resolutely respects himself and, because he does so, respects the rights of others.” The policy opposes any armed intervention in Latin America and aims to reassure the region that the United States will not pursue interventionist policies.

The United States and Mexico face raised tensions in the 1920s as oil companies fear their investments may be expropriated based on language in the Mexican constitution. In August 1923, Mexico and the United States seem to settle the issue by signing the Bucareli Treaty, in which Mexico agrees to respect the rights of U.S. oil companies in exchange for U.S. recognition of the sitting Mexican government. The issue remains a controversial one in Mexico, however, and in 1938, Mexican President Lazaro Cardenas nationalizes the oil industry. The United States does not retaliate out of fear that Mexico will align itself with Germany during World War II, which begins in 1939. Mexico declares war on the Axis powers following the Japanese bombing of Pearl Harbor, and Mexican pilots fight alongside the U.S. Air Force. In 1944, Mexico agrees to pay U.S. oil companies $24 million plus interest for properties expropriated in 1938. Meanwhile, the Mexican government adopts an import-substitution economic strategy, essentially operating as a closed economy.

In August 1942, the United States and Mexico begin their first official labor program for temporary workers. Like the influx of Mexican migrants during World War I, the so-called Bracero Program is a response to a severe wartime labor shortage in the United States. The program, which focuses on the agricultural and railroad industries, mandates a base wage level, housing, medical care, and food, but critics of the program charge that Mexican migrants are exploited by their U.S. employers. Between 1942 and 1964, when the program ends, more than 4.5 million Mexican laborers are sponsored. The program establishes a circular migration pattern for Mexican workers and results in an increase of unauthorized immigration to the United States.

President Harry S. Truman becomes the first U.S. president to visit Mexico City. Later that year, the United States and twenty-one other countries in the Western Hemisphere, including Mexico, sign the Inter-American Treaty of Reciprocal Assistance, or the Rio Treaty. It codifies the "hemispheric defense doctrine," the principle that an attack against one country will be considered an attack against all countries. The Rio Treaty is invoked numerous times during the Cold War, and the United States cites it following attacks on September 11, 2001. In 2002, Mexico becomes the first country to formally withdraw from the treaty in protest over the U.S. intention to invade Iraq.

Concerned about the growing number of unauthorized immigrants in the United States, U.S. President Dwight D. Eisenhower begins Operation Wetback, a forced repatriation program supervised by the Immigration and Naturalization Service (INS). Roughly 750 U.S. Border Patrol agents sweep Arizona and California in June and return them to Mexico by bus and train one month later, it is estimated that fifty thousand people have been apprehended. The INS claims as many as 1.3 million were repatriated during the operation, but this figure includes those who voluntarily returned to Mexico under duress.

The end of the Bracero program—the official temporary worker arrangement started in 1942—in 1964 prompts a flow of migrant workers back to Mexico. In 1965, the Mexican government establishes an industrialization program to create job opportunities for those workers. So-called maquiladoras, or “assembly plants,” are built in border towns to employ low-cost Mexican labor who will assemble goods for the U.S. market. Duty-free raw materials are imported from the United States, and when the finished goods are exported, duty is paid only on the value added. Maquiladoras quickly become labor magnets for Mexicans living further south by 1992, plants employ roughly half a million Mexicans and export $19 billion, about 40 percent of Mexico's global exports. The maquiladora industry strengthens economic and cultural ties between the countries.

After World War II, the Mexican government pushes economic growth through strong public investment in agriculture, transportation, and energy infrastructure, as well as the introduction of high protective tariffs to shield domestic consumer industries. The so-called Mexican Miracle produces 3–4 percent gross domestic product (GDP) growth that lasts for nearly three decades. However, anger at unequal distribution of wealth leads to burgeoning left-wing political forces and spurs social unrest. In 1968, ahead of the Summer Olympics in Mexico City, university students rock the capital with protests and rioting. Ten days before the start of the games, Mexican security forces fire into the crowd at a student demonstration in the capital's Tlatelolco Square. The government estimates the death toll is thirty other sources claim it is closer to two or three hundred.

In September 1969, U.S. President Richard Nixon declares a “war on drugs” and the United States launches an aggressive search-and-seizure counternarcotics operation on the U.S.-Mexico border. Thousands of agents are deployed along the border to inspect “all persons and vehicles crossing into the United States.” As lines at the border grow, Mexico reacts with anger at not being consulted on the operation. In mid-October, the operation is terminated and replaced with a bilateral cooperation agreement between the two countries. In 1973, the United States creates the Drug Enforcement Administration (DEA). There is some counternarcotics cooperation between the two countries in the 1970s and 1980s, but the assassination of a DEA agent in Mexico in 1985 sparks outrage in the United States and leads Washington to pursue a unilateral strategy to fight the war on drugs.

In 1976, massive oil reserves are discovered in the Gulf of Mexico's Bay of Campeche. The Cantarell Field becomes one of the largest in the world, producing more than one million barrels per day by 1981. Mexican President Jose Lopez Portillo pledges to use the nationalized oil industry’s profits to fund economic expansion and social welfare. He borrows huge sums of foreign money and leaves Mexico with the world's largest foreign debt. Meanwhile, U.S. concern over unauthorized immigrants grows. U.S. President Jimmy Carter explores options to overhaul U.S. immigration policy, including improving border security and offering amnesty to undocumented immigrants, but no action is taken.

By 1981, oil prices have fallen, inflation has risen, and Mexico is deeply indebted. The government devalues the peso three times in 1982, resulting in higher inflation and lower real wages. Economic stagnation and widespread unemployment follow, pushing Mexican migrants to cross the border in search of work. In 1986, the United States passes the Immigration Reform and Control Act, which seeks to crack down on undocumented immigration by sanctioning employers who hire unauthorized immigrants. The law also grants amnesty to 2.7 million undocumented workers already in the United States. Unauthorized immigration decreases drastically over the next several years, but picks up again at the start of the 1990s.

Mexico reduces its trade barriers and announces its entrance into the General Agreement on Tariffs and Trade (GATT), the precursor to the World Trade Organization (WTO). Two years later, Carlos Salinas de Gortari, the PRI candidate, is elected president on a reform platform. Salinas pushes to deregulate the economy, paving the way for the North American Free Trade Agreement (NAFTA). In his final year in office, Salinas’s administration is dogged by corruption charges related to drug trafficking.

Who wrote this amazing article?

Hopefully, some history and justice oriented United States Congressperson or Senator will ask for restititution for every agrieved family whose rights were violated under this ruse to empower some greedy, ignorant, low-down person.

Also, all the decendants of the legislators who sponsored the 1879, California Constitution should help with the financial aspects if they are billionaires whose fortunes were made on the backs of the deprived and whose rights were guaranteed by the Treaty of Guadalupe Hilldalgo (and the United States) and International Justice.

Great article base on thruth and justice.
My best,
Charles “Chuck” Pineda, Jr. Retired Parole Board Judge,California
Former Democratic candidate for Governor of California (1986-2010).

Can you please refer me to information about the three-fifths clause and Mexican-Americans after the Mexican-American War. A scholar a couple decades ago told me Mexican-American women and children were not counted as people and men were counted as three-fifths of a person like African-American slaves.

Misspelled truth and didn’t see the error until too late. Anyways here why Mexico lost the war. Spain never recognized Mexican Independence in 1821, as she felt New Spain was to rich to give her up. So, she invaded Mexico three times, and about several years apart. With new cannons from Germany, France, etc. they could hit Mexican army positions and artillery as the new cannons could shoot almost a mile while the old Mexican cannons could only shoot half a mile or less. Even though the Mexicans beat the Spaniards three times leaving several Spanish regiments in Vera Cruz for almost eighteen months before they departed. Casualties of Mexican soldiers was very high. Almost 475 thousand Mexican soldiers were killed, wounded and died, during those three Spanish invasions( Mexican sources).

With almost a half millions men of military age killed during the Spanish invasions Mexico did not have the manpower to defend Tejas/Cuahuila from American or Europeans now American military forces.
Then Santa Ana wrote president Polk a letter indicating if Polk let him enter Mexico he would guarantee that the Mexican Army would not win a single battle. AT THE TIME OF THE WRITTEN NOTE THE UNITED STATES NAVY WAS AFTER SANTA ANA, AND ANY SHIP HEADED TO MEXICO WAS BOARDED AND SEARCHED FOR SANTA ANA, FOR HE WAS TO BE PLACED UNDER ARREST AND TAKEN TO WASHINGTON.

President Polk allowed Santa Ana to enter Mexico and within a few weeks took over the government as he was a very popular figure, and quite handsome! What Santa Ana stated to President Polk came true. The Mexican Army other than the initial battle that started the war lost every battle it fought with American forces. The only battle where the Mexican Army had flanked the American Army was at Buena Vista and was beating the army of Winfield Scott when Santa Ana told his victorious generals to stop the fighting and prepare to march to Vera Cruz as a new American force had landed.
His generals protested violently stating they had the American army on the run, and in a few hours could route them leaving central Mexico in Mexican hands. I believe one general stated it would take three weeks for that new army to unload, organize, and march to support Scott’s army, and, therefore, now was the time for one great victory for the Mexico! Santa Ana overruled them all, and in the morning Scotts army waiting to be attacked and finished off saw no movement for the Mexican Army was gone.

May 13, 1846: U.S. Congress Approves Declaration of War Against Mexico

On May 13, 1846, the U.S. Congress overwhelmingly voted in favor of President James K. Polk’s request to declare war on Mexico in a dispute over Texas.

A proclamation by President Polk at the outset of the Mexican-American War. Source: Library of Congress.

Howard Zinn describes the background to the vote in Chapter 8: “We Take Nothing by Conquest, Thank God'” of A People’s History of the United States. Read short excerpts below and find a longer excerpt in the free classroom lesson listed under Related Resources.

On May 9, before news of any battles, Polk was suggesting to his cabinet a declaration of war, based on certain money claims against Mexico, and on Mexico’s recent rejection of an American negotiator named John Slidell. Polk recorded in his diary what he said to the cabinet meeting:

I stated . . . that up to this time, as we knew, we had heard of no open act of aggression by the Mexican army, but that the danger was imminent that such acts would be committed. I said that in my opinion we had ample cause of war, and that it was impossible . . . that I could remain silent much longer . . . that the country was excited and impatient on the subject.. . .

The country was not “excited and impatient.” But the President was. When the dispatches arrived from General Taylor telling of casualties from the Mexican attack, Polk summoned the cabinet to hear the news, and they unanimously agreed he should ask for a declaration of war.

. . . Polk spoke of the dispatch of American troops to the Rio Grande as a necessary measure of defense. As John Schroeder says (Mr. Polk’s War): “Indeed, the reverse was true President Polk had incited war by sending American soldiers into what was disputed territory, historically controlled and inhabited by Mexicans.”

. . . Congress then rushed to approve the war message. Schroeder comments: “The disciplined Democratic majority in the House responded with alacrity and high-handed efficiency to Polk’s May 11 war recommendations.” The bundles of official documents accompanying the war message, supposed to be evidence for Polk’s statement, were not examined, but were tabled immediately by the House. Debate on the bill providing volunteers and money for the war was limited to two hours, and most of this was used up reading selected portions of the tabled documents, so that barely a half-hour was left for discussion of the issues.

. . . A handful of antislavery Congressmen voted against all war measures, seeing the Mexican campaign as a means of extending the southern slave territory. One of these was Joshua Giddings of Ohio, a fiery speaker, physically powerful, who called it “an aggressive, unholy, and unjust war.” He explained his vote against supplying arms and men: “In the murder of Mexicans upon their own soil, or in robbing them of their country, I can take no part either now or hereafter. The guilt of these crimes must rest on others — I will not participate in them. . . .”

Rethinking Schools editor Bill Bigelow explains the importance of teaching outside the textbook about the U.S. Mexico War:

Today’s border with Mexico is the product of invasion and war. Grasping some of the motives for that war and some of its immediate effects begins to provide students the kind of historical context that is crucial for thinking intelligently about the line that separates the United States and Mexico. It also gives students insights into the justifications for and costs of war today.

Bigelow is the author of a free downloadable lesson called “U.S. Mexico War: “We Take Nothing by Conquest, Thank God’.” The lesson features a reading by Howard Zinn and a role play with many voices on the war typically missing from textbooks such as: Cochise, Colonel Ethan Allen Hitchcock, Frederick Douglass, General Mariano Vallejo, Henry David Thoreau, María Josefa Martínez, Padre Antonio José Martínez, the Saint Patrick’s Battalion, and many more. A version of the lesson is also available in Spanish.

Find the lesson and more resources for teaching about the border below.

Related Resources

U.S. Mexico War: “We Take Nothing by Conquest, Thank God”

Teaching Activity. Lesson by Bill Bigelow and student reading by Howard Zinn. 21 pages. Rethinking Schools.
Interactive activity introduces students to the history and often untold story of the U.S.-Mexico War. Roles available in Spanish.

The Line Between Us: Teaching About the Border and Mexican Immigration

Teaching Guide. By Bill Bigelow. 2006. 160 pages. Rethinking Schools.
Lessons for teaching about the history of U.S.–Mexico relations and current border and immigration issues.

Bound for the Rio Grande: Traitors—Or Martyrs

Background Reading (PDF) and Song. Reading by Milton Meltzer and song by David Rovics. 1974. 4 pages and 5 min.
The story of the San Patricio Battalion, Irish-American soldiers who deserted the U.S. Army during the U.S.-Mexican War and fought on the side of the Mexicans.

The Land That Never Has Been Yet

Podcast. Produced by John Biewen with co-host Chenjerai Kumanyika. 2020. Center for Documentary Studies.
This twelve-part series tells a story of the United States from its beginnings up to the present that questions the traditional narrative about democracy as a foundational value.

San Patricio

Audio. By The Chieftains featuring Ry Cooder. 2010.
Ballads about the San Patricio Battalion during the U.S. Mexico War.

Jan. 28, 1918: Porvenir Massacre

Fifteen Mexican-Americans were killed by Texas Rangers during the Porvenir Massacre.

Watch the video: Today in History:. declares war on Mexico 1846 (January 2022).