Jackson County Cavalry Regiment was organized during the late spring of 1862. Attached to General Shelby's Brigade, Trans-Mississippi Department, it fought at Newtonia, Cane Hill, and Prairie Grove, was a part of Marmaduke's Expedition, and saw action at Helena. Later the unit engaged the Federals in their operations against Little Rock. It sustained 3 casualties at Newtonia, 61 with Marmaduke, and 12 at Helena. The regiment then became the 12th Missouri Cavalry Regiment. The field officers were Colonels Upton Hays and Beal G. Jeans, and Lieutenant Colonels Charles A. Gilkey and David Shanks.