Lecture: The Age of Expansionism 1830-1860

The Age of Expansionism 1830-1860

AP US History

Background • Territorial expansion • Commercial development • Technological progress • “Young America” – spirit of the time: positive attitude toward market economy and industrial growth, a more aggressive foreign policy, and a celebration of virtues

Manifest Destiny • Believe that God had ordained American expansion across the continent • Led to diplomatic confrontations with Britain and Mexico

Land Acquisitions • Webster-Ashburton Treaty, 1842 • Annexation of Texas, 1845 • Oregon dispute settled, 1846 • Treaty of Guadalupe Hidalgo, 1848 • Gadsden Purchase, 1853

Texas Independence • Mexico encouraged American settlement in Texas in the 1820s • Led to problems by 1830s (slavery question, role of Catholic Church), and Mexico, under Santa Anna, moved to quell independence-minded Texans • Texans revolted in 1835-1836. Rallying behind losses at the Alamo and Goliad, Texans defeated Mexico at San Jacinto • General Sam Houston became the first president of the “Lone Star Republic,” independent until 1845

Texas Annexation • Jackson, president at time of Independence, steered clear of annexation debate • President Tyler push for annexation, but Senate voted down the treaty • President Polk successfully campaigned for the annexation of Texas, official in 1845

The Mexican-American War • Mexico refused to recognize Rio Grande as Texas border, and refused to sell land to U.S. • Under Polk’s aggressive expansionist policies, the U.S. declared war on Mexico in 1846 • Under Taylor, Kearney, Fremont, and Scott, the U.S. military quickly prevailed

Treaty of Guadalupe Hidalgo, 1848 • Mexican cession – most of present day New Mexico, Arizona and California for $15 million • Recognition of Rio Grande as border • U.S. government assumes American claims against Mexico • Gasdsen Purchase, 1853, gave U.S. southern most parts of New Mexico and Arizona (potential southern railroad route)

Internal Expansion

• By the 1830s, Americans moved west, attracted by adventure, prospect of financial gain, and (for the Mormons) religious freedom • Americans traveled west on the Santa Fe Trail (1820s) and the Oregon Trail (1840s) • Discovery of gold in California in 1848 led to mass movement westward

Innovation and Expansion • Telegraphs and railroads aided internal expansion (by the 1840s, railroads replaced canals as primary means of internal transport) • Railroad and manufacturing led to boom in industry, more jobs, and more immigration • Agricultural innovations eased farming and led to more settlement • McCormick’s reaper • Deere’s plow

Native Americans on the Frontier • In 1834, the national government passed the Indian Intercourse Act, prohibiting settlers from going on Indian land. • Settlers (and the government) ignored this agreement as economic prospects expanded out west • Government changed their policies several times in the period beyond the Civil War, stay tuned