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The Online Civil War Soldier and Sailors System datbase contains the following summary for this regiment:

9th Regiment, Kentucky Cavalry
9th Cavalry Regiment [also called 4th Mounted Rifles] was organized in December, 1862, by consolidating Breckinridge's and Stoner's Kentucky Cavalry Battalions. The regiment served in J.W. Grigsby's, J.S. Williams', and J.H. Lewis' Brigade, skirmished in Kentucky and Tennessee, and fought in the Atlanta Campaign. It continued the conflict by sharing in the defense of Savannah and the campaign of the Carolinas. A detachment surrendered with the Army of Tennessee, but the main part of the unit escorted President Davis southward and surrendered in May, 1865. Colonel William C.P. Breckinridge, Lieutenant Colonel Robert G. Stoner, and Majors John P. Austin and William E. Jones were in command.