 After his lengthy recovery, he commanded his regiment in the Gettysburg Campaign in Joseph B. Kershaw's brigade, seeing action near the Peach Orchard in the Battle of Gettysburg.However, lingering effects of his wound soon forced Aiken to administrative duty in Macon, Georgia for a year, before he resigned from the Confederate army in mid-1864 and returned home.He was a member of the State house of representatives from 1864–66 and served as secretary and treasurer of the State Agricultural and Mechanical Society of South Carolina in 1869.