Territorial changes of Germany after World War II

The former eastern territories of Germany (German: Ehemalige deutsche Ostgebiete) are those provinces or regions east of the current eastern border of Germany (the Oder–Neisse line) which were lost by Germany after World War I and then World War II.

The territories lost following World War I include most of the Province of Posen and West Prussia, and further territories lost after World War II include East Prussia, Farther Pomerania, East Brandenburg, Upper Silesia, and almost all of Lower Silesia. All territories lost in both World Wars account for 33% of the former German Empire, while land ceded by Germany after World War II constituted roughly 25% of its pre-war Weimar territory. In present-day Germany, the term usually refers only to the territories lost in World War II, while in Poland the territories acquired from Germany after World War II were dubbed the "Recovered Territories" by the Soviet-installed Polish government.

The post-war border between Germany and Poland along the Oder–Neisse line was formally recognized by East Germany in 1950 by the Treaty of Zgorzelec, under pressure from Stalin. In 1952, recognition of the Oder–Neisse line as a permanent boundary was one of Stalin's conditions for the Soviet Union to agree to a reunification of Germany (see Stalin Note). The offer was rejected by West German Chancellor Konrad Adenauer. The official German government position on the status of former eastern territories of Germany vacated by settled German communities east of the Oder and Neisse rivers was that the areas were "temporarily under Polish [or Soviet] administration." In 1970, West Germany recognised the line as a de facto boundary in the Treaty of Warsaw.

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