The original fort was installed on the Arkansas River by Major William Bradford and a company of the Rifles Regiment. Bradford's mission was to stop a bloody war between the Osages and the Cherokees, a conflict discouraging the emigration of eastern Indians to the lands west of the Mississippi and thereby interfering with the government's removal policy.
During the Civil War, Confederate armies at Wilson's Creek, Pea Ridge, and Prairie Grove were supplied from Fort Smith, and the Rebel force that crushed Opothleyoholo's band marched from Fort Smith. The fort was taken by Federal troops in September 1863 and served as a Union base for the remainder of the Civil War.
In 1871 the army again abandoned the fort, but the Federal Court for the Western District of Arkansas soon moved in. Under Judge Isaac Parker, the renowned "Hanging Judge of Fort Smith," the court became a force for law and order in much of Indian Territory.