The Sager orphans were the children of Henry and Naomi Sager. In April 1844 the Sager family took part in the great westward migration and started their journey along the Oregon Trail. During it, both Henry and Naomi died and left their seven children orphaned. Later adopted by Marcus and Narcissa Whitman, missionaries in what is now Washington, they were orphaned a second time, when both their new parents, as well as brothers John and Francis Sager, were killed during the Whitman massacre in November 1847. About 1860 Catherine, the oldest daughter, wrote a first-hand account of their journey across the plains and their life with the Whitmans. Today it is regarded as one of the most authentic accounts of the American westward migration.

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.