Following the defeat of Lieutenant Colonel
George A. Custer on June 25, 1876, in the
Battle of Little Bighorn, the United States government sent a large number of reinforcements into Montana Territory. By autumn, a few bands of the Sioux and Cheyenne tribes had begun returning to the
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 and icy conditions to join the camp of
Crazy Horse in the Tongue River Valley. Concerned with the approaching winter and the destitute condition of Dull Knife's band, Crazy Horse decided to negotiate peace with the army. However, when a group of United States Army Crow scouts murdered Crazy Horse's delegation, the war chief demanded revenge. He led a series of small raids in an effort to draw out Colonel Miles from
Tongue River Cantonment. In December, 1876, Colonel Miles led most of nine Infantry companies out of the Cantonment in pursuit of Crazy Horse, marching south, up the
Tongue River valley. On January 7, 1877, Miles captured a few Northern Cheyennes, then his force of 436 men camped along the Tongue just south of present-day Birney, Montana. During that night a fresh layer of deep snow fell and temperatures dropped. ==Battle==