The Mississippi 4th Infantry Regiment was organized at Grenada as the Fourth Regiment, Second Brigade, Army of Mississippi, and enlisted for twelve months. The Fourth was among the troops posted at Fort Henry on the Tennessee River, under General Lloyd Tilghman. The troops were transferred to Fort Donelson and there captured. Following exchange they were then surrendered at Vicksburg and continued throughout the remainder of the war in the Atlanta Campaign, Franklin, and Nashville, ending the war in the defense of Mobile.