During World War II, Fort Missoula housed an internment camp for Italian detainees, who called the area Bella Vista,[3] and Japanese Americans arrested as "enemy aliens" after Pearl Harbor.

[4] Fort Missoula was established as a permanent military post in 1877 and built in response to requests of local townspeople and settlers for protection in the event of conflict with western Montana Indian tribes.

It was intended as a major outpost for the region; however, area residents also were quite aware of the payroll, contracts, and employment opportunities Fort Missoula would provide.

Construction had barely begun when the Company Commander, Captain Charles Rawn, received orders to halt the advance of a group of non-treaty Nez Perce Indians.

The Nez Perce, led by Chiefs Joseph, Looking Glass and others, simply went around the soldiers' hastily constructed earth and log barricade in Lolo Canyon (later called "Fort Fizzle") and escaped up the Bitterroot Valley.

The soldiers from Fort Missoula, along with other elements of the 7th Infantry and local civilians, attacked the Nez Perce camp at the Battle of the Big Hole, and were defeated and besieged.

[6] The corps undertook several short journeys – up the Bitterroot Valley by bicycle to deliver dispatches, north to the St. Ignatius area, and through Yellowstone National Park – before making a 1,900-mile (3,100 km) trip from Fort Missoula to St. Louis in 1897.

A modern complex of concrete buildings with red tile roofs was constructed between 1908 and 1914, including a new Officer's Row, barracks, and Post Hospital.