With Himmler in charge of the Upper Rhine High Command, the practical effect was that this army group answered directly to Hitler.

What became known as the "Battle of the Bulge" forced the movement of large numbers of U.S. troops north out of Alsace and Lorraine to counter the German attack.

German troops assaulted across the Rhine near Gambsheim on 5 January 1945[4] and soon occupied a bridgehead including the towns of Herrlisheim, Drusenheim, and Offendorf north of Strasbourg.

The Gambsheim Bridgehead, and further to the south, the Colmar Pocket, would not be reduced by Allied forces until well into February 1945, but the operations of the Upper Rhine High Command after mid-January were defensive in nature.

Heinrich Himmler was sent to command Army Group Vistula (Heeresgruppe Weichsel), also on the Eastern Front.