Oregon Trail Opens: 1843 Migration Westward

Nearly a thousand people bet their lives on a rumor that Oregon's Willamette Valley had the best farmland on the continent. On May 22, 1843, approximately 875 emigrants gathered in Independence, Missouri, with 120 wagons and 5,000 head of cattle, and pointed west on a 2,000-mile journey that would take five months and redefine the American frontier. The Great Migration of 1843 was not the first wagon train to Oregon, but it was the first large enough to matter politically. Marcus and Narcissa Whitman had crossed with a small missionary party in 1836, and smaller groups had made the trip since. What made 1843 different was scale: families with children, livestock, furniture, and the full infrastructure of community settlement. The trail ran from Missouri through Kansas, along the Platte River in Nebraska, over the Continental Divide at South Pass in Wyoming, and then northwest through the Snake River plain to the Columbia River. Cholera, river crossings, and exhaustion killed roughly one in ten emigrants on the Oregon Trail over its years of use. The 1843 party lost fewer, partly through luck and partly through the guidance of mountain man Marcus Whitman, who rejoined the train at Fort Hall. The political impact was immediate. Britain and the United States both claimed the Oregon Country, and the question of sovereignty depended partly on which nation's settlers actually occupied the land. The 1843 migration tipped the balance decisively. By 1845, American settlers in Oregon outnumbered British subjects, and the Oregon Treaty of 1846 drew the border at the 49th parallel. Over the next two decades, roughly 400,000 people would travel the Oregon Trail, the largest voluntary overland migration in human history.