Great Sioux Reservation (.pdf)

The Fort Laramie Treaty of 1868 set forth the original boundaries of the Great Sioux Reservation for the Lakota people-- including all of South Dakota west of the Missouri River. The Black Hills region was lost in 1877 as a result of Custer’s defeat at the Little Big Horn. In 1889 it was divided into five smaller reservations (Pine Ridge, Rosebud, Lower Brule, Cheyenne River, and Standing Rock) when South Dakota became a state.