Ziemie Odzyskane

History of Brandenburg and Prussia
Northern March pre–12th century		Old Prussians pre–13th century
Margraviate of Brandenburg 1157–1618 (1806)		Teutonic Order 1224–1525
		Duchy of Prussia 1525–1618	Royal (Polish) Prussia 1466–1772
Brandenburg-Prussia 1618–1701
Kingdom in Prussia 1701–1772
Kingdom of Prussia 1772–1918
Free State of Prussia 1918–1947			Klaipėda Region (Lithuania) 1920–1939 / 1945–present
Brandenburg (Germany) 1947–1952 / 1990–present	Recovered Territories (Poland) 1918/1945–present	Kaliningrad Oblast (Russia) 1945–present

Recovered Territories (Polish: Ziemie Odzyskane, literally "Regained Lands") was an official term used by the People's Republic of Poland to describe the territory of the former Free City of Danzig and the parts of pre-war Germany that became part of Poland after World War II. The rationale for the term "Recovered" was the Piast Concept that these territories were once part of the traditional Polish homeland. They had been part of, or fiefs of, a Polish state during the medieval Piast dynasty. Over the centuries, however, they had become Germanized through the processes of German eastward settlement (Ostsiedlung) and political expansion (Drang nach Osten) and for the most part did not even contain a Polish-speaking minority. Nowadays the term Western Territories (Polish: Ziemie Zachodnie) is more popular because of its ideological neutrality.

The great majority of the German inhabitants either fled or were expelled from the territories during the later stages of the war and after the war ended, although a small German minority remains in some places. The territories were resettled with Polish repatriates forced to leave areas of former eastern Poland that had been annexed by the Soviet Union, with Ukrainians, Rusyns and other minorities forcibly resettled under "Operation Vistula", and with Poles who moved voluntarily from Central Poland. The communist authorities that conducted the resettlement also made efforts to remove many traces of German culture, such as place names and historic inscriptions on buildings, from gained territories.

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Wikipedia