Henry H. Walker age 23 enlisted with his brother Anson Walker on May 7, 1861 at Martinsburg, New York. He mustered in as a Pvt, Company I, 14th Infantry "1st Oneida Regiment" New York volunteers, on May 17, 1861 to serve for two years. He was promoted to Sergeant in January, 1863 and mustered out with Company I on May 24, 1863 at Utica, New York.