On June 25, 1876, U.S. general George Custer(a former officer in the Union army) and the 7th Cavalry of the United States Army arrived at the junction of the Bighorn and Little Big Horn Rivers in eastern Montana. They had come to attack local Sioux and Cheyenne Indians, who, according to inspector E.G. Watkins, were hostile to the United States.

Despite being warned about a tremendous encampment of Indians, Custer divided his regiment into three sections and attacked from the north. Major Marcus Reno attacked from the south. The attacks, however, were ill-advised. Both Reno's and Custer's sections were overwhelmed by the sheer number of Indians led by Crazy Horse. In the end, all 264 U.S. soldiers involved in the attack were killed. General Custer was one of the last to die.