Wood was born in Iowa and served as a volunteer in the Union Army during the American Civil War. He enlisted in the 13th Iowa Volunteer Infantry Regiment on September 17, 1861, and was appointed a corporal in Company F the following month. Following the Battle of Shiloh, in which he was wounded, he was promoted to sergeant, and later participated in the battles of Corinth, Jackson and Meridian in Mississippi. He reenlisted on January 1, 1864, and was made a first sergeant, and campaigned in Georgia and the Carolinas in 1864-65. Wood mustered out at Louisville, Kentucky, on July 21, 1865, as second lieutenant of Company F.