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1846: Smallpox epidemic killed many
1872: Removed to Colville Reservation
Additional References to the History of the Tribe
Frederick Webb Hodge, in his Handbook of American Indians North of Mexico, gave a more complete history of the Sanpoil tribe, with estimations of the population of the tribe at various time periods. Additional details are given in John Swanton's The Indian Tribes of North America.
Wikipedia article on the Sanpoil People