The regiment came under heavy fire at the Battle of Stones River on January 2, 1863. Having been ordered by Bragg to attack an area that division commander Maj. Gen. John C. Breckinridge had reconnoitered and determined to be too heavily defended, the First Kentucky Brigade led the charge. Although initially successful, the brigade was met by heavy Union Army artillery fire. Brigade commander Brig. Gen. Roger Hanson was also mortally wounded in the attack. The 9th Kentucky Infantry lost one killed and twenty-eight wounded in the battle.