From 1815, the area appeared of minimal strategic importance, as it lay deep within the borders of the German Confederation and (from 1871) of the German Empire, and German military planning presumed any war would be effectively lost long before an enemy reached that far into the homeland. The route became important again at the end of World War II when the U.S. XII Corps used it in their advance eastward in late March and early April 1945. The U.S. advance had little consequence for Germany's strategic position (which was indeed hopeless by that point), but it allowed the Americans to occupy vast swaths of territory which the Yalta Conference of February 1945 had assigned to the Soviet occupation zone. This in turn did much to compel the Soviets to honor their commitment to allow the Western Allies access to Berlin in exchange for U.S. withdrawal (July 1945) from this territory.