The expulsion of Poles by Germany was a prolonged anti-Polish campaign of ethnic cleansing by violent and terror-inspiring means lasting nearly half a century. It began with the concept of Pan-Germanism developed in the early 19th century and culminated in the racial policy of Nazi Germany that asserted the superiority of the Aryan race. The removal of Poles by Germany stemmed from historic ideas of expansionist nationalism. It was implemented at different levels and different stages by successive German governments. It ended with the defeat of Nazi Germany in 1945.

Following the Invasion of Poland at the beginning of World War II, nearly a quarter of the entire territory of the Second Polish Republic was annexed by Nazi Germany and placed directly under the German civil administration. The rest of Nazi-occupied Poland was renamed as the General Government district. The annexation was part of the "fourth partition of Poland" by Nazi Germany and the Soviet Union, outlined months before the invasion, in the Molotov–Ribbentrop Pact.