Harris served as a private in Company F of the 149th Indiana Infantry Regiment, which occupied Decatur, Alabama in 1865. He enrolled at Terre Haute, Indiana, on February 15, 1865 at the age of twenty. Harris records his experiences as a soldier and traces his journey south to Decatur. Harris also describes his interactions with locals in North Alabama, writing in April 1865 that he "halted to talk with a family of Rebbs questioning concerning their so-called independence but found out nothing of importance Except that ther hopes had fled." He also includes descriptions of skirmishes in which he took part, as well as lengthy descriptions of the terrain and weather. Harris adds his comments on the assassination of Abraham Lincoln and writes down song lyrics and poetry at points. Harris was discharged on September 27, 1865.
