Fort Harrison was established in 1892 and remained active through World War I. It was named for President Benjamin Harrison, who served in Congress in 1799 and died one month after taking the office of the President of the United States. In 1906, the fort was officially named Fort William Henry Harrison. By 1922, the fort was given to the Veteran's Administration and is now a hospital for veterans. The first post office was established in 1899 with Martha Hodel as postmaster.
Fort Harrison is located in southwestern Montana, north of Helena off U.S. Highway 12.