This painting appears to be a late work given its soft contours, invented subject matter and weak deliniation of form.  The primary Indian figure in the composition seems to be launching his canoe into a lake, not the Little Big Horn River, so the title does not conform with the subject.  The composition and style of this oil conforms with other fanciful late paintings by Sharp like Apache Ambush - Arizona (related image, #373)

In 1948, Sharp reworked an old canvas of a similar theme, titled it Night Gigging and sold it to Thomas Gilcrease.  (see related image, #386)