Reuben Mitchell was born around 1844 in England to William and Mary Mitchell. The family immigrated to America around 1855 and settled in Cuyahoga County, Ohio. By 1860, his father was working as a farmer and owned $100 of personal property. Mitchell enlisted in the Union army on January 10, 1862, and mustered in as a private in Company E of the 54th Ohio Infantry later that day. The regiment took part in the Battles of Shiloh, Corinth, and Chickasaw Bayou. Mitchell, however, fell ill early in 1863 and died in Jefferson Barracks near St. Louis, Missouri, on April 28, 1863.