The papers and photographs in this collection document the history and customs of the Piegan Indians (also known as the Blackfeet Indians) in Montana, and their contact with Europeans and Anglo Americans. The collection provides detailed information about McClintock's photographic practice, as well as his public presentations about the Piegan Indians. A significant part of the collection records the development and production of Poia, an opera based on Piegan Indian legends, composed by Arthur Finley Nevin, with a libretto by Randolph Hartley (1870-1931).