Most of the Brumfields from Louisiana served in Wingfield's 3rd Louisiana Cavalry, also known as the 9th Louisiana Partisan Ranger Battalion. There may be a dozen or so. About twenty Brumfields enlisted in Mississippi units, many from Pike County. Isaac Brumfield joined Co. "K", but we do not know when.

Isaac Brumfield enlisted in one of the "Minute Men" companies assigned to Quinn's 2nd Mississippi State Regiment. It was organized in Pike County by Capt. Magee for twelve months service. Isaac Brumfield enrolled at Holmesville MS, June 5, 1862, and appointed 3rd Corporal. The roll for Feb. 28, 1863, reports that he had been absent without leave since Dec. 10, 1862. For that reason alone, we can be certain that he was not present with his command during that period. That much can be disputed but not disproven.