By early 1945, Nazi Germany was on the verge of total military collapse. Poland had fallen to the advancing Soviet Red Army, which was preparing to cross the Oder between Küstrin and Frankfurt-an-der-Oder with the objective of capturing Berlin to the west. German forces had recently lost to the Allies in the Ardennes Offensive, with British and Canadian forces crossing the Rhine into the German industrial heartland of the Ruhr. U.S. forces in the south had captured Lorraine and were advancing towards Mainz, Mannheim, and the Rhine. German forces in Italy were withdrawing north, as they were pressed by the U.S. and Commonwealth forces as part of the Spring Offensive to advance across the Po and into the foothills of the Alps.