The Sioux resent the emigrant route Bozeman…
1866 CE
When the Army builds forts to protect the trail, the Crows cooperate with the garrisons.
On December 21, 1866, the Lakota, Cheyenne, and Arapaho defeat Captain William J. Fetterman and his men from Fort Phil Kearny.
Evidently, the United States cannot enforce respect for the treaty borders agreed upon fifteen years before.