History 110
Whose Manifest Destiny?  The Conquest of Northern Mexico

Map of Mexican American War

Discussion Goals:

  1. To understand the economic, social, and political status of Mexico at the time of American immigration.
  2. To examine the causes that led up to the Mexican American War and the way it contributed to the growth of the U.S. at Mexico’s expense.
  3. To study the consequences of the Mexican American War.
  4. To learn how the Mexicans fared in “Occupied Mexico” - that portion of Northwest Mexico that came under control of the US after 1848.

Excerpt from a Mexican textbook on the annexation of Texas an the U.S. intervention in Mexico, as presented in the book, As Others See Us.

"Texas was annexed to the United Staes by the treaty of April 12, 1844, despite the protests of our [Mexican] government and even though the treaty was rejected by the American Congress. Thereupon the annexation of the territory was proposed in the House and approved on March 1, 1845, which forced our Minisster in Washington to withdraw. The Texans, backed by the American government, claimed that its boundaries extended to the Rio Bravo del Norte [Rio Grand], whereas in fact the true limits had never passed the Nueces River. From this [boundary dispute] a long controversy developed [during which negotiations were carried on] in bad faith by the Americans.

Map of Mexico in 1836

They ordered trooops to invade places within our territory, operating with the greatest treachery, and pretended that it was Mexico which had invaded their territory, making Mexico appear as the aggressor. What they were really seeking was to provoke a war, a war in which the southern states of the Union were greatly interested, in order to acquire new territories which they could convert into states dominated by the slavery interests. But since the majority of the people in the United States were not pro-slavery nor favorable of a war of conquest, President Polk tried to give a defensive character to his first military moves, foreseeing the opposition which he would otherwide encounter. Once he obtained a declaration of war, Polk made it appear that he wanted nothing more than peaceful possession of the annexed territory...

The Mexican War was a brilliant move astutely planned by the United States. The magnificent lands of Texas and California with their ports on both oceans, the gold deposits soon to be discovered in the latter state, and the increase in territory which made possible the growth of slave states compensated the United States many times over the costs in men and money of the unjust acquisition..."


Goal #1: To understand the economic, social, and political status of Mexico at the time of American immigration

Map of Mexico at the time of Mexican independence and the year that Stephen Austin's immigrant party came to Mexico in 1821 - a year in which Rodopho Acuna notes the new nation was "bankrupt, and it needed time to build an infrastructure to unify the new country."

Map Mexico 1821


Goal #2: To examine the causes that led up to the Mexican American War and the way it contributed to the growth of the U.S. at Mexico’s expense

Causes of the Mexican American War

  1. U.S. government adopted an aggressive foreign policy designed to force Mexico to sell Texas.
  2. North American immigration to Texas, eventually making Americans the dominant population.  
  3. American refusal to submit to Mexican laws.
  4. Mexico adopted a new, centralized government, thus forcing the Mexican states to relinquish some of their power.
  5. Anglo-American settlers sought more autonomy of Texas.
  6. Americans established the Republic of Texas with the western boundary at the Nueces River.
  7. The U.S. government annexed Texas with the western bourndary at the Rio Grande River.

First Cause - The U.S. government adopted an aggressive foreign policy designed to force Mexico to sell Texas.

American interest in Texas will really heat up after two things are accomplished:

  1. a significant number of Americans had moved into Texas territory - enough to stimulate a move for independence; and
  2. a president with deeply expansionist ambitions moves into the White House.

Second Cause - Americans began immigrating to the Mexican territory of Texas and quickly became the dominant population.

Third Cause - American refusal to submit to Mexican laws

Fourth Cause - Mexico adopted a new, centralized government, thus forcing the Mexican states to relinquish some of their power.Drawing of President Santa Anna

Fifth Cause - Anglo American settlers' began to seek more autonomy for Texas.

Sixth Cause - Americans established the Republic of Texas with the western boundary at the Nueces River.

Seventh Cause - The U.S. government annexed Texas with the western boundary at the Rio Grande River.

Map of Mexican cession of land after Mexican American War

 

Massachusetts Protests the Mexican American War, 1847

"Resolved, That the present war with Mexico has its primary origin in the unconstitutional annexation to the United States of the foreign state of Texas ...; that it was unconstitutionally commenced by the order of the President, to General Taylor, to take military possession of territory in dispute between the United States and Mexico, and in the occupation of Mexico; and that it is now wage ingloriously, - by a powerful nation against a weak neighbor - unnecessarily and without just cause, at the immense cost of treasure and life, for the dismemberment of Mexico, and for the conquest, of a portioin of her territory, from which slavery has already been excluded, with the triple object of extending slavery, of strengthening the "Slave Power," ob obtaining the control of the Free States, under the Constitution of the United States.

Resolved, That such a war of conquest, so hateful in its objects, so wanton, unjust, and unconstitutional in its origin an character, must be regarded as a war against freedom, against humanity, against injustice, against the Uniion, against the Constitution, and against the Free States; and that a regard for the true interests and the highest honor o the country, not less than the impulses of Christian duty, should arouse all good citizens to join in efforts to arrest this gigantic crime, by withholding supplies, or other voluntary contributions, for its further prosecution; by calling for the withdrawal of our army within the established limits of the United States; and in every just way aiding the country to retreat from the disgraceful position of agression which it now occupies toward a weak, distracted neighbor and sister republic."


Goal #3: To study the consequences of the War
  1. More than 12,000 lives were lost.
  2. U.S. spent more than $100 million dollars.
  3. The U.S. acquired a colony that was 1 million acres (55% of all Mexico) and contained rich farmlands and natural resources such as gold, silver, zinc, copper, oil, and uranium, as well as new ports that would facilitate economic expansion across the Pacific.
  4. Disagreements over slavery escalated across the United States. A growing number of northerners were convinced that the War was started by southern slave owners who wanted to open the newly acquired lands to slavery.
  5. American political parties were weakened and subsequently, it became increasingly difficult for the nation's leaders to prevent slavery and the expansion of slavery from dominating Congressional activity for the next 12 years. We can especially see this with the controvery that began in 1845 over the Wilmot Proviso.
  6. It was one of the most unpopular wars in U.S. History. Opposition to the War was mostly among abolitionists who felt that the war was being fought to expand slavery. Among those who opposed the war were:

"Plucked" political cartoon showing how the U.S. plucked Mexico as a result of the Mexican American war


Goal #4: To learn how the Mexican population fared in "Occupied Mexico" Political Cartoon of Occupied Mexico

The Mexicans who now lived in what many began to call "Occupied Mexico" did not fare well.

Mexican Land Dispossession in California

Map of California Land Grants under Mexican ruleThe early 1820s until the Gold Rush - Spanish and Mexican rulers granted over 800 large tracts of California land to Hispanic and white settlers. The rulers did not recognize Indian ownership of these lands. Newcomers to California selected valley locations with rich soil and reliable water sources to raise livestock and crops. Most grants were not accurately surveyed and mapped, which made the claims difficult to prove when California passed into American hands in 1848.

1848 - The Treaty of Guadalupe Hidalgo that formally ended the Mexican American War provided that the Mexican land grants would be honored (Article X). However, the United States Senate removed that protection when ratifying the Treaty. In order to investigate and confirm titles in California, American officials acquired the provincial records of the Spanish and Mexican governments.

In the ten years before the missions were dismantled, the Mexican government had issued only 50 grants for large ranchos. In the dozen years after the missions were secularized, over 600 new grants were made.
1851 - The California Legislature passed an "Act to Ascertain and Settle Private Land Claims in the State of California" which required all holders of Spanish and Mexican land grants to have their land titles confirmed by the newly-created Board of California Land Commissioners. Despite promises in the Treaty of Guadalupe Hidalgo, this Act placed the burden of proof of title on Spanish and Mexican landholders - and this was a difficult burden because in most cases, the land grants were made without closely defining the exact boundaries and even when boundaries were more specific, many markers had been destroyed before accurate surveys were made.

Although 604 of the 813 claims brought before the Land Commission were confirmed, most decisions were appealed to US District Court and some even went to the Supreme Court. The confirmation process required lawyers, translators, and surveyors, and took an average of 17 years to resolve - making it very expensive to defend land titles. In many cases, land had to be sold to pay for defense fees or given to attorneys in lieu of payment.

From the early 1850s forward - Before 1850, Mexican Californios owned all the land valued at over $10,000.