After the Second World War , the Soviet Union annexed the Polish territory of the Kresy — located east of the Curzon line — and encouraged or forced ethnic minorities in these parts of Poland , including ethnic Poles , to move west . In the framework of the campaign , Soviets exhibited posters in public places with messages such as , During the Cold War the official position in the First World was that the concluding document of the Potsdam Conference was not an international treaty , but a mere memorandum . It regulated the issue of the German eastern border , which was to be the Oder-Neisse line , but the final article of the memorandum said that the final status of the German state and therefore its territories were subject to a separate peace treaty between Germany and the Allies of World War II . During the period from 1945 to 1990 two treaties between Poland and both East and West Germany were signed concerning the German-Polish border . In 1950 the German Democratic Republic and the People 's Republic of Poland signed the Treaty of Zgorzelec , recognizing the Oder-Neisse line , officially designated by the Communists as the " Border of Peace and Friendship " . On 7 December 1970 the Treaty of Warsaw between the Federal Republic of Germany and Poland was signed concerning the Polish western border . Both sides committed themselves to nonviolence and accepted the existing '' de facto '' border - the Oder-Neisse line . However a final treaty was not signed until 1990 as the " Treaty on the Final Settlement With Respect to Germany "
Potsdam Conference
Potsdam Conference
Recovered Territories