In 1862 there was a bloody uprising of the Minnesota Sioux. Hostilities spread to the Plains, with grave danger to lines of communication and army outposts with garrisons depleted by the Civil War. During this period, Fort Laramie was a headquarters post, occupied during the crucial years principally by the 11th Ohio Volunteer Cavalry, under Col. William O. Collins. There was a chain of outposts up and down the North Platte, from Mud Springs near present Bridgeport to South Pass, Wyo. These were frequently harassed by Sioux and Cheyenne warriors. One of these beleaguered outposts was adobe-walled Fort Mitchell, about 2 miles northwest of Mitchell Pass. Initially called “Camp Shuman” for its builder and first commander, Capt. J. S. Shuman, it was constructed in 1864, according to official records, and was last heard of in 1867. The little fort (and later nearby “Scott’s Bluffs Pass”) was named for Brig. Gen. Robert B Mitchell (1823-82), commander of the Nebraska Military District, a citizen of Kansas Territory who earlier fought gallantly in the Civil War and later became Governor of New Mexico Territory. Fort Mitchell saw its share of frontier action. Colonel Collins’ report of 1865 to the regimental adjutant advises: Co H has been Stationed at Fort Mitchell 55 Miles East of Laramie on the Platte River. The company participated in the celebrated Indian fights at Mud Springs and Rush Creek where 150 Men under Command of Lt Col Wm O Collins fought from fifteen hundred to two thousand of the dusky warriors, since that time this Company has carried the Mail from Julesberg to Laramie. This has been heavy and laborious duty, yet they have never flinched but have had the Mail through in good time. Besides this company has built one Mail Station, near the noted Land Mark Chimney Rock, besides repairing the one at Mud Springs. [Illustration: _Cavalrymen leaving Fort Mitchell._ Original sketch in Oregon Trail Museum.] [Illustration: _William H. Jackson sketch of Fort Mitchell at Scotts Bluff._] The Battle of Mud Springs in February 1865 was an aftermath of the siege of Julesburg by a horde of Sioux and Cheyenne who were enraged by a massacre of Cheyennes at Sand Creek, Colo. In zero weather the small garrison at Fort Mitchell joined Colonel Collins’ forces in an attempt to intercept the north-bound Indians. After skirmishing and light casualties, the Indians withdrew across the North Platte.