The Sioux are made up of three divisions of language dialects. The Santee people speak Dakota, the Yankton people use Nakota, and the Teton people speak Lakota. The people of the Sioux Nation refer to themselves as Lakota, Dakota, or Nakota, words which all mean "friend" or "ally."

During the 16th and 17th centuries, the Sioux Nation lived in part of present day North Carolina. They migrated westward on foot and by small boats, hunting small animals and gathering edible plants. By about 1700, they reached the Missouri River and then onto the flat, treeless region of the Great Plains. By the early 19th century, the Sioux Nation dominated most of the Dakotas, northern Nebraska, eastern Wyoming and southeastern Montana. Within these boundaries, the Sioux people roamed freely. They spent their lives hunting buffalo, gathering food, and adapting to their new environment.

The Sioux developed a culture based on the principle of living in harmony with nature and the environment. Through a rich oral tradition, they passed on their values, beliefs, and spirituality, including tales of the buffalo, a sacred animal that provided almost everything the people needed to stay alive. The nomadic tribes followed the patterns and movements of the herds as they migrated across the Plains.

As a warrior society, Lakota tribes often fought over territory with enemy tribes such as the Cree, the Chippewa, and the Crow. With the arrival of horses on the Plains, there came a new focus for intertribal conflict. A successful horse thief earned the respect of his band. In the face of growing numbers of non-native settlers on the Plains in the 1800s, tribes began forming alliances to protect their territory. The U.S. government responded to conflict with a set of treaties to create reservations for native peoples. The territory promised to the Sioux in 1868 was soon divided into several smaller reservations that would continue to decrease in size through allotment policies.

Today, many Sioux people living on reservations face harsh conditions with high levels of poverty, unemployment, and teen suicide. For some however, it is a time of optimism. Several reservations are bringing back herds of buffalo for subsistence and cultural use. Many tribes are experiencing a period of sociopolitical change, population growth, and a cultural revival including the return of traditional ceremonies such as the Sun Dance.