Bates was born to Alpheus Bates (1808 - 1888) and Hannah Bates (1810 - 1901) on 17 March 1840. Bates enlisted with the 121st New York Infantry in August 1862. He was captured at the Battle of Salem Church during the Battle of Fredericksburg and was held at Libby Prison in Richmond, Virginia for approximately two weeks. He was subsequently released in a prison exchange. He was also involved in the battles of Chancellorsville and Gettysburg.