Pearl River County was formed after the Civil War from parts of Hancock and Marion Counties, and Confederate units raised in those parent counties included in Hancock County Capt. Robards' Company, Company G, 3rd Battalion Infantry Minute Men; Gainesville Volunteers, Company G, 3rd Mississippi Infantry; Hancock Rebels, Company C, 38th Mississippi Infantry [Mounted]; Poitevent's Company, Company B, 17th Battalion Mississippi Cavalry; and Shieldsboro Rifles, Company F, 3rd Mississippi Infantry; and in Marion County the Columbia Guards, Company I, 38th Mississippi Infantry [Mounted]; Jeff Davis Sharpshooters, Company D, 7th Mississippi Infantry; Marion Grays, Company G, 2nd Mississippi Infantry Minute Men; and Marion's Men, Company F, 7th Mississippi Infantry. The Hancock Rebels were formed at Hobolochitto, now known as Picayune, and were the city's only known Confederate unit. They served at the battles of Iuka and Corinth and during the 47 day Siege of Vicksburg. Originally an infantry unit, they were mounted in 1864 and served under Confederate General Nathan B. Forrest at the Battle of Harrisburg, Mississippi. Twenty-one Rebels died during the war.