The Potsdam Conference of 1945 defined the Oder-Neisse line as the border between Germany and Poland, pending a final peace conference with Germany which eventually never took place. At the end of WWII, Germans in Silesia fled from the battle ground, assuming they would be able to return when the war was over. However, they could not return and those who had stayed, were expelled and new Polish population from Central Poland, or themselves forcibly re-settled from the Soviet Union took their place. After 1945 and in 1946, nearly all of the 4.5 million Silesians of German descent fled, or were interned in camps and forcibly expelled, including some thousand German Jews who survived the Holocaust and had returned to Silesia.