The Sioux can be found throughout the northern Plains, including North and South Dakotas, northern Nebraska, eastern Wyoming, and southeastern Montana. The arrival of white Americans following the Louisiana Purchase lead to an end to native Sioux life due to the depletion of the buffalo. There are three native Sioux dialects, Dakota, Lakota and Nakota. Biggest and most famous of these is Lakota.
Zitkala-Sa was a Yankton Sioux woman. She was well educated and went on to become an accomplished author, musician and composer - she wrote the first American Indian opera, The Sun Opera, in 1913. She went on to work for the reform of Indian policies in the United States