The eight day Sun Dance was held every summer before the Plains Indians began buffalo hunting.
Most tribes of the plains held their own ceremonies, including the Lakotas, Cheyennes, Blackfeet, Shoshones, and Arapahos.
In the Sun Dance, an individual made pledges.
For example, if an illness was cured or an injury repaired during the year, the person could do a Sun Dance as a thanksgiving offering to the gods responsible for the good fortune.
With these pledges, the tribe restored good will to itself and reestablished the productive forces of nature.