This is the order of battle of German and Allied forces during the Battle of the Bulge — specifically, at a point near the end of the battle, which lasted from 16 December 1944 until 25 January 1945. As with any large Army organization in extended combat, forces and their assignments shifted over the course of the battle. For example, when the German attack began on 16 December, the U.S. 7th Armored Division was assigned to XIII Corps, U.S. Ninth Army, 12th Army Group. Later that day, its alignment became VIII Corps, U.S. First Army, 12th Army Group. On 20 December, the alignment switched to XVIII Corps, U.S. First Army, 12th Army Group — and later that day to XVIII Corps, U.S. First Army, 21st Army Group. On 18 January 1945, the alignment changed one last time, to XVIII Corps, U.S. First