Is there any way of telling what unit a person was attached to during the Civil War? Written accounts state that my GG-Grandfather was a dispatch rider and scout for the Union Army. He probably enlisted toward the end of 1862 since he had "a years worth of stories", he lived in Henry County and rode about 15 miles to meet up with his unit in Calhoun during the time of Price's Raid. He apparently rode with a man named John Gordon who had worked for him and one of his former slaves, Charles, apparently joined the same unit as a cook. All this being said, I am finding it to be an intimidating task to figure out where to begin looking for Drury Bagwell Revis on the Union Troop rosters. Does anybody have any ideas where to start?