Wikipedia
Sihasapa
The Sihásapa or Blackfoot Sioux are a division of the Lakota people, Titonwan, or Teton.
Sihásapa is the Lakota word for "Blackfoot", whereas Siksiká has the same meaning in the Blackfoot language. As a result, the Sihásapa have the same English name as the Blackfoot Confederacy, and the nations are sometimes are confused with one another.
The Sihásapa lived in the western Dakotas on the Great Plains, and consequently are among the Plains Indians. Their official residence today is the Standing Rock Reservation in North and South Dakota and the Cheyenne River Reservation in South Dakota, home also to the Itazipco (No Bows), the Minneconjou (People Who Live Near Water) and Oohenumpa (Two Kettle), all bands of the Lakota.