William P. Winn was born in Tennessee in approximately 1846 and served in Company D, 18th USCT during the war. The 18th USCT was organized in Missouri in 1864 and participated in the Battle of Nashville. It also guarded railroads in Bridgeport, Alabama, and in Chattanooga. After the war, Winn moved to Monticello, Illinois, where he worked as a barber. He was also a member of the Monticello GAR Post. He died in Monticello on 26 January 1901 and is buried in Mt. Hope Cemetery, Urbana.