Fort Washita was established in 1842 in the Choctaw Nation, Indian Territory, as the southwestern-most military post of the United States. The mission of the soldiers was to protect the recently immigrated Choctaw and Chickasaw Indians. The fort was later used during the Civil War. Today, many buildings still stand, along with scattered remnants of foundations and several cemeteries. Visitors are encouraged to tour the museum, located near the entrance to the grounds.