Preston's MO Cavalry Bn operated as an independent unit until it was consolidated with Burbridge's Bn to form the 4th MO Cav Regt by Special Orders 41, HQ Trans-Miss Dept, on 11 Feb 1863. The order reads: "The Battalions of Col. Burbridge and Major Preston (Missouri troops) having been consolidted and formed into a regiment, the following appointments are made subject to the approval of the War Department. Jno Q. Burbridge, Col; William J. Preston, Lt. Colonel; Dennis Smith, Major. By order of Lt Gen Holmes, S. S. Anderson, AAG