Montana during the War with Plains Native American Tribes
Rand McNally and Company 1881
By the late 1870s, the conflicts between Plains Native American tribes and the U.S. Army had escalated to all-out war. Hostile tribes were considered “the enemy” and were treated as such. Fort Custer, which had originally been called “The Big Horn Post,” grew into a major fort. Captain Erasmus Corwin Gilbreath’s duties there were extensive. The presence of many important army officers underscored the intentions of the U.S. Army in their campaigns against Native American tribes.
Not every tribe engaged in warfare with the Army. Some, like the Crow, sold off much of their land in treaty agreements with the United States and settled more or less peaceably on large reservations.