CLEARWATER, Fla. – On March 18, 2023, Blackwell Auctions will offer a painting of one of the most historically important figures of the 19th century, Lakota chief Sitting Bull (1831-1890). American history will forever denote Sitting Bull as the dynamic military, spiritual and political leader who united the Sioux people to defeat US General George Armstrong Custer at Little Big Horn in 1876.