Robert Gray first enlisted in Co. G, 1st Arkansas Regiment 30-Day Volunteers, at Evening Shade, Arkansas, on November 15, 1861, for thirty days; and was discharged at Camp Borland, Pocahontas, Arkansas, on December 15, 1861. This was a hastily-organized regiment which was organized to counter a reported Union invasion of northeast Arkansas that never came off.

He next enlisted in (new) Co. C, 27th Arkansas Regiment Infantry, at Lunenburg, Arkansas, on July 12, 1862, by Capt. J. M. Wood, for three years or the war; age 25; appointed fifth sergeant, December 23, 1862; appointed third lieutenant, May 27, 1863; granted leave of absence for fifteen days, August 14, 1863, by surgeon’s certificate and endorsed by colonel and brigadier-general; assigned to duty, per Special Orders, No. 172, District of Arkansas, October 1, 1863; wounded (lost left leg) at Mansfield, Louisiana, April 8, 1864; paroled at Natchitoches, Louisiana, June 14, 1865; he listed his residence as Batesville, Arkansas.

He applied for a Confederate pension from Izard County in 1911 (pension no. 19251 approved August 10, 1911). His widow applied for a Confederate pension from Izard County in 1915 (approved August 13, 1915).