Theme: American continental expansionism gained great momentum in the 1840s, leading first to the acquisition of Texas and Oregon, and then to the Mexican War, which added vast southwestern territories to the United States and ignited the slavery question.
As Tyler assumed the presidency after Harrison’s early death, the United States became engaged in a series of sharp disputes with Britain. A conflict over the Maine boundary was resolved, but British involvement in Texas revived the movement to annex the Lone Star Republic to the United States.
The Texas and Oregon questions became embroiled in the hotly contested 1844 campaign, as the Democrats nominated and elected the militantly expansionist Polk. After Texas was added to the Union, Polk pursued an aggressive policy of expansion. Unable to obtain Mexican California peaceably, Polk led the nation into war with an equally belligerent Mexico in 1846.
American forces quickly conquered California and New Mexico. Winfield Scott’s and Zachary Taylor’s invasion of Mexico was also successful, and the United States obtained large new territories in the peace treaty.
Besides adding California, New Mexico, and Utah to American territory, the Mexican War trained a new generation of military leaders and aroused long-term Latin American resentment of the United States. But its most important consequence was to force the slavery controversy to the center of national politics, as first indicated by the Wilmot Proviso proposing to ban slavery from the newly acquired territories.
developing the chapter: suggested lecture or discussion topics
Explain the movement toward expansion in relation to the theories of American “Manifest Destiny” and “mission.” The focus might be on how the drives to acquire Oregon, Texas, and California arose from the general belief that America should expand across the continent.
reference: Ray Billington, Westward Expansion (1974).
Examine the role of women in the westward expansion of the 1840s to Oregon and elsewhere. Compare their outlooks and concerns to those that dominated the “manifest destiny” ideology.
reference: Susan Butuille, ed., Women’s Voices from the Oregon Trail (1994).
Consider the origins of the Mexican War in relation to Polk’s desire for California and the narrow issue of the Texas boundary. Analyze the charges by the war’s opponents that Polk’s essential aim was to add new slave territory to the United States. Consider the long-term results of the Mexican War.
reference: Patricia Nelson Limerick, The Legacy of Conquest (1987).
Examine the Mexican War in relation to broader patterns of ethnic and racial conflict in the Southwest.
reference: Reginald Horsman, Race and Manifest Destiny (1981).
for further interest: additional class topics
Discuss the role of Texas and California in the buildup to the Mexican War. Consider whether the war could have been avoided had the Mexicans agreed to sell California to the United States.
Focus on the Manifest Destiny campaign of 1844. Discuss whether Polk had a “mandate” for expansionism and, if so, whether he successfully fulfilled the American majority’s goals in the West.
Use Lincoln’s “spot resolutions” or Thoreau’s “Civil Disobedience” essay to highlight the opposition to the war, particularly the charge that Polk had maneuvered to bring on the fighting.
Consider the Mexican War from a Mexican perspective. Discuss the long-term consequences of acquiring the “Spanish borderlands” for both Mexicans and Americans.
Thomas Hart Benton (1782–1858)
Benton, the most prominent Jacksonian Democratic senator of the early nineteenth century, was a grand spokesman for national greatness and the common person.
Having grown up on the Tennessee frontier, he moved to St. Louis in 1815 and became editor of the second newspaper printed west of the Mississippi. In his youth he was involved in numerous duels, including one in which he and his brother nearly killed Andrew Jackson. He later became one of Jackson’s closest political allies.
Benton was a huge man with great energy and long-winded speaking capacity. When not orating in the Senate, he undertook speaking tours of up to a thousand miles on horseback, and huge crowds gathered to hear him talk for two or three hours. Mark Twain used one of Benton’s visits to Hannibal, Missouri, as the basis for an episode in Tom Sawyer.
Like most Jacksonians, Benton tried to divert national attention away from the slavery issue, thinking that it would disappear. But he harshly condemned southerners who threatened secession over slavery.
Quote: “I shall not fall on my sword, as Brutus did…but I shall save it, and save myself, for another day, and for another use—for the day when the battle of the disunion of these states is to be fought—not with words but with iron—and for the hearts of the traitors who appear in arms against their country.” (Senate speech, 1844)
reference: William Chambers, Old Bullion Benton: Senator from the New West (1956).
James K. Polk (1795–1849)
Polk was the dark-horse presidential winner of 1844 who carried out his ambitious program of Manifest Destiny.
The scion of a stern Scots-Irish family, he was very serious and fanatically hardworking, never able to relax or get away from politics.
He was Andrew Jackson’s leader in the House of Representatives during the Bank War. Although called a dark-horse nominee in 1844, Polk was actually a very well known Democrat and would probably have been the vice-presidential candidate with Van Buren in 1844 if the former president had not opposed the Texas annexation.
During his presidency Polk operated almost entirely alone, having no personal friends, and his diaries show that he was often secretive and manipulative. He exhausted himself with overwork and died only a few months after leaving office.
Quote: “After repeated 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 at war.…War exists, and notwithstanding all our efforts to avoid it, exists by the act of Mexico herself.…” (War Message to Congress, 1846)
reference: Sam W. Haynes, James K. Polk and the Expansionist Impulse (1997).
Antonio López de Santa Anna (1795–1876)
Santa Anna was the Mexican military dictator who lost both the Texas war for independence and the Mexican War.
The uneducated son of a minor Spanish bureaucrat, Santa Anna emerged from the turmoil of the independence movement to dominate Mexican politics. He was an unscrupulous manipulator and opportunist who ruled by granting favors to the army and exploiting the peasant masses. When not at war, Santa Anna spent most his time in cockfighting and gambling. He loved to stage fantastic, expensive public entertainments, which he would attend with his numerous mistresses.
He lost a leg defending Vera Cruz against a French raid in 1838 and used this sacrifice as proof of his patriotism when it was questioned. He was frequently driven into exile in Cuba and Colombia but usually managed to return to power when civilian politicians led the country to chaos.
Quote: “Mexicans! You have a religion—protect it! You have honor—free yourself from infamy! You love your wives, your children—then liberate them from American brutality!” (Appeal to the Mexican populace, 1847)
reference: Robert Schenia, Santa Anna (2002).
Winfield Scott (1786–1866)
Scott, the American commander in the Mexican War, was the most important U.S. military leader between the Revolution and the Civil War.
Scott first became a national hero as a young officer in the War of 1812, when he was wounded in the Battle of Lundy’s Lane. He fought in several Indian wars in the 1830s before becoming head of the army in 1841. He was called “Old Fuss and Feathers” because of his love for military pomp and detailed regulations. His campaign from the coast at Vera Cruz over the mountains to Mexico City is still considered a military masterpiece. During the year in which he ruled the city under military occupation, he was considered very fair and just by the Mexicans.
Although he had a decent understanding of politics from a military perspective, his Whig candidacy for the presidency in 1852 was doomed by sectional conflict within the party. He was still holding on as the aged commander of the U.S. army at the outbreak of the Civil War, but was shortly replaced.
Quote: “The object of all our dreams and hopes, toils and dangers—once the gorgeous seat of the Montezumas. That splendid city will soon be ours!” (Speech to troops, 1847)
reference: James McCaffrey, Army of Manifest Destiny (1992).
questions for class discussion
1. Was American expansion across North America an “inevitable” development? How was the idea of Manifest Destiny used to justify expansionism?
2. Why was the Texas annexation so controversial? What would have happened had Texas remained an independent nation?
3. What caused the Mexican War? Did Polk provoke the Texas-boundary conflict in order to gain California or expand slavery, as war opponents like Lincoln charged?
4. What were the benefits and costs of the Mexican War both immediately and in the longer run of American history?
1. What distinctive features of Spanish and Mexican society and culture affected the early history of settlement in California?
2. In what ways was the Californios’ experience of being forcibly incorporated into the United States similar to that of voluntary immigrants, and in what ways was it different?
Suggested Student Exercises
Use a map of California to discover Spanish place names. Consider why it is misleading to assume that all such names derive from the pre-1848 Californios.
Compare this early history of California settlement with the later image of California as a golden land of youth and excitement. Consider which features of the Californios’ actual historical experience have been incorporated into this romantic vision of California, and which have not.