Montana's Historic Forts and Battlefields

In the 1860s Euro-Americans poured into Montana, lured by stories of rich gold strikes and aided by the completion of the Mullan Road and the Bridger and Bozeman trails. As they encroached on Indigenous land and the U.S. government sanctioned treaty violations, conflict became inevitable.


Montana Territory featured several significant battles of the Indian Wars. These included the 1876 Battle Where the Girl Saved Her Brother/Battle of the Rosebud, where the Lakota and the Tsétsėhéstȧhese/Só'taeo'o (Northern Cheyenne) successfully impeded General George Crook’s advance from Wyoming and the better-known Battle of the Greasy Grass/Battle of the Little Bighorn. The Nez Perce War of 1877 also saw several major battles, including the Battles of the Big Hole and Bear Paw; the former was a military win for the Nimiipuu (Nez Perce), while the latter was the war’s final fight.


These conflicts led the U.S. government to construct military forts across the territory. Posted soldiers served the dual purpose of protecting nearby communities and suppressing Native American uprisings. Fort Assinniboine was especially active, tasked with keeping the Ne-i-yah-wahk (Cree) and Métis in Canada and engaging in the last military conflict with Tȟatȟáŋka Íyotake (Sitting Bull) and his people.


By the 1900s, Montana tribes had ceded 92 percent of their former territory. With Native Americans confined to reservations, the federal government decommissioned many of Montana’s forts. Only two—Fort Harrison and Fort Missoula—served military purposes through World War II. Fort Harrison was the training ground for the American–Canadian First Special Service Force, an elite unit that served in the Pacific and European theaters. Fort Missoula became an internment camp, first for Italians and later for Japanese-Americans.


Buildings that remain at historic forts show the architectural impact of the Army Quartermaster General’s Standardized Plans of the late 1800s. Uniform in size, mass, and materials, they also reflect the aesthetics of their era.


As of 2022, only Fort Harrison serves a military purpose. However, the forts’ presences—no matter how diminished—are reminders of early colonizer-Indigenous relations in Montana. Contained within their construction is the U.S. government’s determination to drive the Indigenous peoples from their lands.

The U.S. Army’s final attempt to remove nontreaty Nez Perce (or Niimiipuu, pronounced Nee-me-poo) from their homeland in northeast Oregon in the summer of 1877 launched their 1,170-mile flight. It culminated at Bear Paw Battlefield south of present-day Chinook. Although the nontreaty Niimiipuu had…
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The New Deal’s National Recovery Administration provided funds for the construction of several significant buildings at the fort in the 1930s. These included a dairy barn, milk house, cattle sheds, and this large horse barn. Designed and built in 1934 by the U.S. Bureau of Animal Husbandry at a…
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According to the United States War Department, Fort Assinniboine was established in 1879 “for the purpose of protecting the citizens of Montana from the hostile incursions of Indian tribes dwelling in that region; and especially … the Sioux which had withdrawn across the international boundary line…
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In the 1870s, the U.S. Army dotted the territory with forts as it worked with brutal efficiency to confine Indians to reservations. With that mission well underway by the 1880s, it closed most of its nine Montana forts and decided to consolidate operations at a new location. Eager to benefit…
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