Following the unconditional surrender of German forces on May 8-9, 1945, and military occupation by the Allies, the victors of World War II officially assumed “supreme authority” in Germany on June 5, 1945. It was above all the United States and the Soviet Union, newly emerged from the war as “superpowers,” that determined the basic direction of Germany in international politics for almost half a century until the revolution of 1989 and Germany's reunification on October 3, 1990. Germany was caught in the center of the tensions produced by the East-West conflict. Particularly in the period from 1945 to 1968, this meant a high degree of dependency until detente and a new policy toward the East changed the underlying conditions and created greater freedom of action for the Federal Republic of Germany and the German Democratic Republic (GDR).
from four power control to partition
The beginning of the postwar period in Germany was completely overshadowed by Allied Four Power control. Plans for partition that had been considered during the war initially played no part following the Yalta Conference in February 1945. The victors were unable to agree on a partition strategy because the expert commissions from the United States and Great Britain, in the course of their planning for Germany in 1943-4, had come to the conclusion that breaking up Germany would have serious disadvantages for the reintroduction of economic and political stability in postwar Europe. At the last wartime conference of the Big Three, from July 17 to August 2, 1945, in Potsdam, an express agreement was made “to treat Germany as a single economic unit” and to set up central administrative units that could serve as the core of a new all-German government.