This was Andersonville

McElroy, with a detachment of his regiment, was guarding a supply route to Cumberland Gap when his entire company was captured in a surprise attack one morning during the winter of 1862-63. He and his comrades were taken to Lippy Prison, and from there they were sent to Andersonville. McElroy spent the rest of the war as a prisoner. His story of attempts at escape, of comrades tracked through cypress swamps by packs of vicious dogs, and of the everyday struggle just to stay alive, is one of the great stories of the Civil War.