Settlers begin trekking across the continent to…

Settlers begin trekking across the continent to Oregon Territory, above the northernmost boundary of the Mexican Republic, and to California, below it, in the early 1840s.

Missionary Marcus Whitman, returning from the East to Oregon in 1843, helps lead the first large group of wagon trains west from Fort Hall, in eastern Idaho.

Known as the "Great Emigration", it establishes the viability of the Oregon Trail for future homesteaders.