Key Events and Concepts of U.S. Expansionism

Manifest Destiny

1840s - The belief that the United States was destined to expand across the North American continent from the Atlantic to the Pacific.

Oregon Trail

1830s-1860s - A 2,000-mile route used by settlers traveling to the Oregon Territory in the 1840s and 1850s.

Tejanos

Early 1800s - Mexican residents of Texas, particularly those who lived in the region before Texas became part of the United States.

General Santa Anna

1794-1876 - Mexican general and president, prominent during the Texas Revolution and the Mexican-American War.

"Remember the Alamo"

1836 - Rallying cry during the Texas Revolution, referencing the battle where Texian defenders were killed by Mexican forces.

Lone Star Republic

1836-1845 - The independent nation of Texas after it gained independence from Mexico, before becoming part of the U.S.

Texas Annexation

1845 - The process by which Texas became the 28th U.S. state after its independence from Mexico.

President John Tyler

1790-1862 - The 10th president of the U.S., known for pushing the annexation of Texas.

President James Polk

1795-1849 - The 11th president, known for overseeing the Mexican-American War and U.S. territorial expansion.

"54'40 or Fight"

1844 - Slogan used by U.S. expansionists advocating for the northern boundary of Oregon Territory at the 54°40′ parallel.

Oregon Treaty

1846 - Agreement between the U.S. and Britain that set the boundary between U.S. and British territories in the Pacific Northwest.

Mexican-American War

1846-1848 - War between the U.S. and Mexico following the annexation of Texas, leading to U.S. territorial gains in the Southwest.

Treaty of Guadalupe Hidalgo

1848 - Treaty that ended the Mexican-American War, ceding a vast amount of land from Mexico to the U.S.

Gold Rush

1848-1855 - The mass migration to California following the discovery of gold at Sutter's Mill in 1848.

Wilmot Proviso

1846 - Proposal to ban slavery in any territory acquired from Mexico after the Mexican-American War, though it was never passed.

Free-Soil Party

1848-1854 - Political party that opposed the expansion of slavery into the western territories.

Popular Sovereignty

1850s - Doctrine that allowed settlers of U.S. territories to decide whether to permit slavery, proposed by Stephen A. Douglas.

Compromise of 1850

1850 - Series of laws aimed at resolving slavery disputes, including California's admission as a free state and the Fugitive Slave Act.

Fugitive Slave Act

1850 - Law that required runaway slaves to be returned to their owners, even if they had escaped to free states.