In 1861 he returned to America and enlisted in Company D, Third Kentucky Infantry, Confederate. He was wounded in Shiloh along with seeing action in Mississippi and Louisiana, before a transfer to the 46th Virginia at the request of his father to Henry Alexander Wise. While in the 46th was in Charleston, South Carolina, he was commissioned to create thirty one paintings of the city’s defenses by Brig. Gen. Thomas Jordan, chief of staff to commanding Gen. General Beauregard. This was part of a campaign by Beauregard to increase support for his ideas about the defense of the harbor in the Confederate government.
In 1863, he was transferred to the 59th Virginia Infantry, as an ordnance sergeant. In 1864, Conrad was furloughed for six months and traveled to Italy. After the end of the war, unable to reconcile to the Confederacy’s loss, Conrad traveled to Mexico for a short while. He moved his family to Richmond in 1898 around which time he sold 31 paintings to then Confederate Memorial Literary Society, which later became the Museum of the Confederacy.
Conrad created art while he was in active duty during the Civil War. While there were several artists on the Union side who captured the war in painting, which were also active, this was not the case on the Confederate side.