On June 25-26, 1876, Lieutenant Colonel George Armstrong Custer led approximately 700 men of the 7th Cavalry Regiment against a large encampment of Lakota, Northern Cheyenne, and Arapaho along the Little Bighorn River in Montana Territory. The engagement was part of the Great Sioux War, sparked by the U.S. government's attempt to seize the Black Hills after gold was discovered there in 1874, violating the 1868 Fort Laramie Treaty. Warriors led by Crazy Horse, Sitting Bull, and Chief Gall defeated Custer's divided force, killing 268 soldiers including Custer.