During the Civil War, Frederick became a major center for caring for the wounded after the battles of South Mountain, Antietam, Gettysburg, and Monocacy. In this building, doctors embalmed soldiers who died in area hospitals and prepared them for burial at nearby Mount Olivet Cemetery or for shipment home. The building's owner, James Whitehill, was both a furniture maker and undertaker, and Dr. Richard Burr, a contractor with the U.S. Army, performed embalming here and gave public demonstrations of the new process on Sunday afternoons. The Hessian Barracks at the south end of Frederick served as a U.S. general hospital throughout the entire Civil War, and after nearby battles, makeshift hospitals were established in virtually every large structure, from barns in the surrounding countryside to churches downtown. After the Battle of Antietam, some 8,000 wounded soldiers recuperated in Frederick at a time when the town's population was 8,000. Dr. Jonathan Letterman's revolutionary triage system for sorting and treating the wounded based on the severity of their wounds was first used here after the battles of South Mountain and Antietam, and his system remains in use today.