In the catalogue for Sharp's retrospective exhibition at the Gilcrease Foundation in 1949, Sharp wrote a comment about Gall. "A Chief of the Hunkpapa Sioux and a leader of the Sioux in the Battle of the Little Big Horn, in which he displayed remarkable military skill. Gall was born in 1840 and died in 1894." Sharp did not paint among the Sioux until 1900, so this portrait must have derived from a historic photograph.