The Great Sioux Nation is the traditional political structure of the Sioux in North America. The peoples who speak the Sioux language are considered to be members of the Oceti Sakowin (Očhéthi Šakówiŋ, pronounced ) or Seven Council Fires. The seven-member communities are sometimes grouped into three regional/dialect sub-groups (Lakota, Western Dakota, and Eastern Dakota), but these mid-level identities are not politically institutionalized. The seven communities are all individual members of the historic confederacy. In contemporary culture, the designation is primarily a linguistic, cultural, and for some, political grouping. Since 2019, Sioux language has been an official language of South Dakota. Subdivisions The Great Sioux Nation is divided into three linguistically and regionally based groups and several subgroups. Linguistically, all three language groups belong to the Sioux language. Lakota (also known as Lakȟóta, Thítȟuŋwaŋ, Teton, and Teton Sioux) Northern Lakota (Húŋkpapȟa, Sihásapa) Central Lakota (Mnikȟówožu, Itázipčho, Oóhenuŋpa) Southern Lakota (Oglála, Sičháŋǧu) Western Dakota Yankton (Iháŋktȟuŋwaŋ) Yanktonai (Iháŋktȟuŋwaŋna) Eastern Dakota (also known as Santee-Sisseton or Dakhóta) Santee (Isáŋyáthi: Bdewákhathuŋwaŋ, Waȟpékhute) Sisseton (Sisíthuŋwaŋ, Waȟpéthuŋwaŋ) The term "Great Sioux Nation" is also sometimes applied to the region (and hypothetical state) of the western and midwestern United States which, while not a legal designation, includes the following recognized Indian reservations: Oglala (Pine Ridge Indian Reservation) Sićangu (Rosebud Indian Reservation) Hunkpapa (Standing Rock Indian Reservation/Cheyenne River Indian Reservation) Minniconjou (Cheyenne River Indian Reservation) Sans Arc (Cheyenne River Indian Reservation) Two Kettles (Cheyenne River Indian Reservation) Crow Creek Indian Reservation Lower Brule Indian Reservation Santee Indian Reservation Yanktonai (Yankton Sioux Indian Reservation) Flandreau Indian Reservation Lake Traverse Indian Reservation (Sisseton-Wahpehton) Lower Sioux Upper Sioux Shakopee-Mdewakanton Prairie Island Standing Rock Indian Reservation Spirit Lake Tribe (formerly Devil's Lake Reservation) This region also includes the defunct Great Sioux Reservation, which was divided into smaller portions in the 19th century, and other "unceded Indian territory" in four states, as well as parts of the following states: Montana Nebraska North Dakota South Dakota Wyoming The Great Sioux Nation occupies only parts of the United States where Sioux tribes have some legal claim with regard to treaties with the federal government, e.g., Treaty of Fort Laramie. Historically, the Great Sioux Nation and the United States have had a turbulent relationship. The last of the great American Indian battles – the Battle of Little Bighorn and the Wounded Knee Massacre – were fought between these two peoples. Controversy In one of the