the outbreak of World War II in September 1939, the Soviets annexed a massive portion of the eastern part of Poland (November 1939) in the wake of an August 1939 agreement between the Reich and the USSR. During the German occupation of Poland during World War II (1939-1945), the Nazis forcibly resettled ethnic Germans from other areas of Central Europe (such as the Baltic states) in the pre-war territory of Poland. At the same time the Nazi authorities expelled, enslaved and killed Poles and Jews. After the Nazis' defeat in 1945, Poland did not regain its Soviet-annexed territory; instead, Polish communists, directed by the Soviets, expelled the remaining Germans who had not been evacuated or fled before from the areas of Lower Silesia, Upper Silesia, Pommerania, East Brandenburg, and East Prussia and made Poles take their place, some of whom were expelled from Soviet-occupied areas that had previously formed part of Poland. About half of East Prussia became the newly created Soviet territory of Kaliningrad Oblast (officially established in 1946), where Soviet citizens replaced the former German residents. Claims to a border along the Oder-Neisse line were presented at the Potsdam Conference of August 1945 by a delegation of Polish politicians. The Potsdam Conference's results eventually specified or endorsed the shifting of borders pending a later Peace Treaty. In the following years, the communists and activists inspired by the Myśl zachodnia strived to "de-Germanize" and to "re-Polonize" the huge land, propagandistically termed Recovered Territories. Following the downfall of the Polish Communist regime in 1989, the German minorities' political situation in modern-day Poland has improved, and after Poland joined the European Union in the 2004 enlargement and was incorporated into the Schengen Area, German citizens are now allowed to buy land and property in the areas where they or their ancestors used to live, and can return there if they wish. However, none of their properties have been returned after being confiscated. A possible demonstration of the ambiguity of the Polish-German minority position can be seen in the life and career of Waldemar Kraft, a minister without portfolio in the West German Bundestag during the 1950s. However, most of the German minority had not been as involved in the Nazi system as Kraft was. There is no clear-cut division in Poland between the Germans and some other minorities, whose heritage is similar in some respects due to centuries of assimilation, Germanisation