As with other emigrant trails in the west, the Bozeman Trail followed a route previously used by traders, trappers, and Native Americans. John Bozeman, along with John Jacobs, officially opened the Bozeman Trail to emigrants in 1863. This 500-mile trail shortened travel from Fort Laramie to the Montana gold mines by half, provided adequate water and food, cut through the hunting grounds of the Sioux, Cheyenne, and Arapaho tribes, and broke the terms of the 1851 Fort Laramie Treaty. This treaty promised the lands of the Power River Basin to Native Americans.
The great Sioux chief, Red Cloud, led his warriors against the emigrants traveling the Bozeman Trail. The United States responded in 1865 and 1866 by building military forts along the trail. While emigrant travel declined sharply after 1866, Native American hostilities persisted and the forts remained opened until 1868, when a new Fort Laramie Treaty was signed. The new treaty re-established the Native Americans possession of the Powder River lands. However, in only six years, the discovery of gold in the Black Hills created conflict, and the Native Americans ultimately lost control of the lands the Bozeman Trail crossed. The trail continued to be used as a military and freight road and by local travelers into the 20th century.