Oder–Neisse line

The Oder–Neisse line is the basis of the international border between Germany and Poland. It runs mainly along the Oder and Lusatian Neisse rivers and meets the Baltic Sea in the north, just west of the ports of Szczecin and Świnoujście .
All prewar German territories east of the line and within the 1937 German boundaries – comprising nearly one quarter of the 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 , was allocated to the Soviet Union as the Kaliningrad Oblast of the Russian SFSR . A part of the German population in these territories – estimated at approximately 12 million as of autumn 1944 – had fled the advance of the Red Army.

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