The 263rd Coast Artillery was called up for Federal service on 13 January 1941 and spent World War II manning the defenses of Charleston Harbor.

[2] Under the Pentomic reorganization of the South Carolina Army National Guard, the three Florence units were consolidated as the headquarters company of the 3rd Battle Group of the 118th Infantry on 1 April 1959.

[3] In May 1969 the 132nd and 133rd Military Police Companies were called up for state active duty in response to the 1969 Charleston hospital strike.

[7] The battalion headquarters participated in two-week annual training at Fort Stewart during the summer of 1973 together with other South Carolina Army National Guard units of the 2nd Brigade, 30th Infantry Division.

[8] As of 2010 it also included the 131st Military Police Company at Beaufort,[9] converted in 2008 from Troop B, 202nd Cavalry as a result of the elimination of the 218th Infantry Brigade.