 The 4th CBW administratively controlled only two groups until December 1943, when the newly arrived 447th BG was assigned to it.In 1944, some subordinate units attacked coastline defenses and marshalling yards in preparation for the Allied invasion of France.Some units supported ground troops during the Battle of the Bulge (December 1944 – January 1945) and the assault across the Rhine (March 1945 – April 1945).