to as many as 80,000. In August the Soviets placed the city under the control of German communists. Following the Yalta Conference held in February 1945 where the new geopolitics of Central Europe were decided, the terms of the Potsdam Conference decreed that with almost all of Lower Silesia, the city would become part of Poland in exchange for Poland's loss of the city of Lwów along with the massive territory of Kresy in the east, which was annexed by the Soviet Union. The Polish name of Wrocław was declared official. There had been discussion among the Western Allies to place the southern Polish-German boundary on the Glatzer Neisse, which meant post-war Germany would have been allowed to retain approximately half of Silesia, including west bank of Breslau. However, the Polish government insisted the border be drawn at the Lusatian Neisse farther west. 1945–present Following World War II, the region became part of Poland under territorial changes defined by the Potsdam Agreement. The town's inhabitants who had not fled, or who had safely returned to their home town after the war officially had ended, were expelled between 1945 and 1949 in accordance to the Potsdam Agreement and were settled in the Soviet occupation zone or in the Allied Occupation Zones in the remainder of Germany. The city's last pre-war German school was closed in 1963. The Polish population was dramatically increased by the resettlement of Poles during postwar population transfers during the forced deportations from Polish lands annexed by the Soviet Union in the east region, some of whom came from Lviv (Lwów), Volhynia, and the Vilnius Region. A small German minority (about 1,000 people, or 2% of the population) remains in the city, so that today the relation of Polish to German population is the reverse of what it was a hundred years ago. Traces of the German past, such as inscriptions and signs, were removed. In 1948, Wrocław organized the Recovered Territories Exhibition and the World Congress of Intellectuals in Defense of Peace. Picasso's lithograph, La Colombe (The Dove), a traditional, realistic picture of a pigeon, without an olive branch, was created on a napkin at the Monopol Hotel in Wrocław during the World Congress of Intellectuals in Defense of Peace. In 1963, Wrocław was declared a closed city because of a smallpox epidemic. In 1982, during martial law in Poland, the anti-communist underground organizations Fighting Solidarity and