After WWII, the ex-German territory was annexed by the Soviet Union and Poland. The Germans were largely evacuated in 1944-45 already, and after 1945 they were expelled by the new authorities.

It is estimated that 16 million Germans left these territories which were subsequently resettled by people from the lost territories of Poland (from the lost East to the "regained" West) and the Soviet Union (in case of Königsberg area).