The Biographical Souvenir of the States of Georgia and Florida, published in 1889, pp. 196-197, has the following entry: M. R. Cooper was born in Columbia County, Florida on 10 January 1846. In spring 1861, he enlisted in Company K, 2nd Florida. In the reorganization of the regiment just after the battle of Williamsburg, Cooper was made color bearer, until the battle of Frazier's Farm in June 1862, when he was severely wounded in the right arm and subsequently discharged.