After the Civil War, increased westward migration resulted in escalating violent conflict between the Plains Indian tribes protecting their ancestral lands and the new settlers. The 1867 Medicine Lodge Treaty failed to quell the violence, which resulted in Maj. Gen. Philip Sheridan’s new strategy of attacking the tribes in their winter camps. In November 1868, Lt. Col. George Custer’s troops marched out of Camp Supply and initiated a surprise attack on Cheyenne Peace Chief Black Kettle’s village on the Washita River. The battle, also referred to as a massacre, was the opening salvo in the US Army’s five-month campaign to force the Cheyenne into living on reservations.