11th Cavalry Battalion was organized during the winter of 1862-1863. It was formed by reducing MacDonald's Missouri Cavalry Regiment. The unit served in C. Greene's Brigade, Trans-Mississippi Department, and fought at Helena and Bayou Fourche before being merged into the 10th Missouri Cavalry Regiment. Its field officers were Lieutenant Colonel Merritt L. Young and Major George W. C. Bennett. Consolidated with Lawther's Tenth Cavalry Regiment.