LTC Elliott was appointed captain and commanding officer of Co. H, 102nd Ohio Volunteer Infantry, on July 23, 1862, and just before leaving for the field he was married to Emily, the daughter of Zenas Crane. He was promoted to major on March 6, 1863 and to lieutenant colonel on April 23, 1864. On 24 September 1864, while the regiment was stationed at Decatur, AL, he was placed in command of three hundred men--all that could be spared--to march in relief of Ft. Henderson near Athens, AL, that was under siege by confederate cavalry under the command of CSA Gen. Nathan Bedford Forrest. Within three miles of Athens Elliott's command was met by General Forrest with a greatly superior force. His little band fought and drove back many times its own number and would have entered the fort had it not been surrendered before their arrival. Elliott's force had maneuvered to within a quarter of a mile of it when its guns were turned upon them and he was met by a fresh brigade of rebels under General Warren. Soon his ammunition was gone and he was completely surrounded. At this juncture General Warren commanded his orderly to "shoot that officer" (pointing to LTC Elliott) and a moment later he fell mortally wounded in the head. He lingered for nineteen days under the care of a family in a nearby home, but the ball could not be extracted. Most of the time he was wildly delirious, talking almost constantly of wife and home, but during his lucid intervals he gave good evidence that he was conscious of his approaching death and that he was sustained and soothed by an unfaltering trust in his savior Jesus Christ. He was a member of the Presbyterian Church, having made a profession of his faith in February 1862. He died of his wounds on October 13, 1864, and his body was buried near Athens. There is no evidence that he was wounded by Forrest himself as the gravestone inscription might seem to indicate. This gravestone was executed in Wooster, Ohio, apparently commissioned by the LTC's widow Emily, and sent to his original gravesite. When the LTC's remains were disinterred and reburied in the Stones River National Cemetery the gravestone was also moved there.
After the war, Emily visited the home of the people in Athens who had cared for her husband, thanking them and giving them gifts.