Yount served two terms in the Union Army during the American Civil War. He first enlisted for a six-month term in November 1861. He was wounded and taken prisoner by the Confederate States Army in an opening skirmish of the Battle of Pea Ridge in Arkansas in March 1862, and held as a prisoner of war for nearly a month until released in a prisoner exchange. He re-enlisted in August 1862 and served until the end of the war. He was promoted three times and was a company quartermaster sergeant when he was discharged in July 1865.