I don't know much about the 15th Conf. Cav. Here is a little something though:

"The Fifteenth Confederate Cavalry was engaged in the Battle of Blakley, the last major battle of the war, in Baldwin County, Al. The regiment disbanded at the downfall of the Confederacy, except two or three companies, which were paroled at Demopolis." Source: http://members.aol.com/dixieideals/15thCC.htm