Marcus Whitman was an American physician and missionary. He is most well-known for leading settlers across the Oregon Trail, unsuccessfully attempting to Christianize the Cayuse Indians, and being killed by the Cayuse Indians in the Whitman massacre.

The Oregon Trail was a 2,170-mile (3,490 km) east–west, large-wheeled wagon route and emigrant trail in the United States that connected the Missouri River to valleys in Oregon Territory. The eastern part of the Oregon Trail spanned part of what is now the state of Kansas and nearly all of what are now the states of Nebraska and Wyoming. The western half of the trail spanned most of the current states of Idaho and Oregon.