In the early spring of 1864, Keller was reported sick in hospital in Savannah.
Pvt. Keller was captured June 11, 1864 near Louisa Courthouse, Va. He was sent to Fortress Monroe, Va. on June 20th and moved to Point Lookout, Md.
Pvt. S.W. Keller was exchanged on November 1, 1864.