 In September 1862, he joined Company G, 12th Vermont Infantry, serving as its captain, and was mustered out with his regiment in July 1863.After he returned home, Ormsbee started practicing law in Brandon, as a partner of Anson A. Nicholson, and later with Ebenezer N. Briggs.He was appointed assistant United States internal revenue assessor in 1868, serving until 1872.