Westward expansion, Manifest Destiny & Native America
Manifest Destiny, continental expansion from Louisiana to the Pacific, and federal Indian policy from removal to allotment, as tested on the FSOT.
The acquisition of a continent
The United States quadrupled its territory in six decades through a sequence of purchases, treaties, and wars the FSOT expects you to name precisely. The Louisiana Purchase (1803), negotiated by Robert Livingston and James Monroe for roughly $15 million, doubled the national domain and forced Thomas Jefferson—a strict constructionist—to concede that the Constitution contained no express power to acquire territory, which he justified under the treaty power. The Adams-Onís Treaty (1819) secured Florida from Spain and fixed the transcontinental boundary to the Pacific. The annexation of Texas (1845) by joint resolution under President John Tyler precipitated the Mexican-American War (1846-1848), concluded by the Treaty of Guadalupe Hidalgo (February 2, 1848), which transferred the Mexican Cession—California, Nevada, Utah, and parts of Arizona, New Mexico, Colorado, and Wyoming—for $15 million and assumption of claims. The Oregon Treaty (1846) with Britain set the 49th parallel boundary, and the Gadsden Purchase (1853) added the southern strip of Arizona and New Mexico for a rail route.
Manifest Destiny as ideology
The phrase "Manifest Destiny" was coined by journalist John L. O'Sullivan in the Democratic Review in 1845, asserting the nation's God-given right "to overspread the continent allotted by Providence for the free development of our yearly multiplying millions." The doctrine fused Protestant providentialism, Jacksonian democracy, and Anglo-Saxon racial ideology. It rationalized the displacement of Mexicans and Native nations and justified the annexationist program of the Polk administration.
The mechanics of settlement
Federal land policy engineered settlement. The Northwest Ordinance (1787) had established the template: survey, territorial government, then statehood on equal footing. The Homestead Act (1862) granted 160 acres to settlers who improved the land for five years; the Pacific Railway Acts (1862, 1864) chartered the Union Pacific and Central Pacific, whose lines met at Promontory Summit, Utah, on May 10, 1869, binding the continent and accelerating the destruction of the bison economy. The Morrill Land-Grant Act (1862) endowed agricultural colleges from public land.
Expansion was never politically neutral. Each acquisition reopened the question of slavery's extension: the Missouri Compromise (1820), the Wilmot Proviso (1846), the Compromise of 1850, and the Kansas-Nebraska Act (1854) all turned on whether new territory would be slave or free. Frederick Jackson Turner's "Frontier Thesis" (1893), delivered after the Census Bureau declared the frontier closed in 1890, argued that the frontier had forged American democracy and individualism—a thesis the FSOT may test as historiography, not settled fact.