Oceti Sakowin

The Great Sioux Nation was the political structure of the Sioux in North America at the time of their contact with Europeans and Euro-Americans. Most of the peoples speaking a Siouan language were members of the Očhéthi Šakówiŋ (pronounced [oˈtʃʰetʰi ʃaˈkowĩ]) or Seven Fires Council. The seven members are sometimes grouped into three regional/dialect groups (Lakota, Western Dakota, and Eastern Dakota), but these mid-level identities were not politically institutionalized. The seven smaller groups were separate members of one confederacy.

The Great Sioux Nation is divided into three linguistically and regionally based groups and several subgroups. Linguistically, all three language groups belong to Siouan languages.

The term "Great Sioux Nation" is also sometimes applied to a hypothetical state in the western and midwestern United States, which would take in the following recognized Indian reservations:

The hypothetical state would also include 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:

The theoretical 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. (See, e.g., Treaty of Fort Laramie and map of treaty land in the External links section below.)

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.

In one of the oldest, unresolved cases in US legal history, United States v. Sioux Nation of Indians 448 U.S. 371 (1980), the U.S. Supreme Court ruled that the United States was wrong in breaking the terms of the Fort Laramie Treaty of 1868, which forever exempted the Black Hills from all-white settlement. When European Americans discovered gold there in 1874, miners swept into the area in a gold rush. The US government reassigned the Lakota, against their wishes, to other reservations in western South Dakota, breaking up the Great Sioux Reservation into smaller portions.

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Wikipedia