Following the defeat of George Armstrong Custer in the 1876 Battle of Little Bighorn, by autumn, only a few bands of the warring Sioux and Cheyenne tribes had begun filtering back into their reservations and agencies to acquire food and annuity goods in preparation for winter. The United States Congress had angered many Indians by demanding that they cede the Black Hills to the government in exchange for these promised goods. The army had replaced civilian contractors in charge of the agencies, further convincing many war bands to stay away from them. General Nelson Miles led a mixed force of infantry, artillery and cavalry after Sitting Bull's band, and had effectively defeated them by December. Ranald S. Mackenzie had similarly defeated Dull Knife's Cheyennes, who trekked through snow an