All prewar German territories east of the line and within the 1937 German boundaries – comprising nearly one quarter (23.8 percent) of the (pre-Nazi) Weimar Republic – were annexed under border changes promulgated at the postwar Potsdam Conference, with most becoming part of Poland. The small remainder, consisting of northern East Prussia with the German city of Königsberg (now renamed Kaliningrad), was allocated to the Soviet Union as the Kaliningrad Oblast of the Russian SFSR (today Russia). Nearly all of the German population in these territories – estimated at approximately 12 million as of autumn 1944 – fled or were later expelled.