Kresy

Eastern Borderlands

Kresy Wschodnie
Part of the Second Polish Republic
In the 1939 German-Soviet Molotov–Ribbentrop Pact the Kresy (grey) were annexed directly into the Soviet Union. The gains east to the Curzon line devised in 1919 were confirmed (with minor adjustments in the areas around Bialystock and Premysl) by the Western Allies at the Tehran conference, the Yalta conference and the Potsdam conference. In 1945 most of Germany's territory east of the Oder-Neisse line (pink) was ceded to what remained of Poland (white), both of which would comprise the newly created People's Republic of Poland
Historical region
Period	1919 – 1945
Area	Territories of Poland annexed by the Soviet Union in the Invasion of Poland of 1939

Kresy Wschodnie or Kresy (Polish pronunciation: [ˈkrɛsɨ], Eastern Borderlands, or Borderlands) was a historical region of the Second Polish Republic during the interwar period constituting nearly half of the territory of the state; where the ethnic Poles, being the largest group, were roughly equal in their number to the size of the national minorities (with notable exceptions). Administratively, the territory of Kresy was composed of voivodeships of Lwów, Nowogródek, Polesie, Stanisławów, Tarnopol, Wilno, Wołyń, and the Białystok. Today, these territories are divided between Western Ukraine, Western Belarus, and south-eastern Lithuania, with such major cities as Lviv, Vilnius, and Grodno no longer in Poland. In the Second Polish Republic the term Kresy roughly equated with the lands beyond the so-called Curzon Line, which was suggested after World War I in December 1919 by the British Foreign Office as the eastern border of the re-emerging sovereign Republic following the century of partitions. In September 1939, after the Soviet Union joined Nazi Germany in their attack on Poland in accordance with the Molotov–Ribbentrop Pact, the territories were incorporated into Soviet Ukraine, Belarus and Lithuania in the atmosphere of terror.