Socialist bloc

The Eastern Bloc was the group of communist states of Central and Eastern Europe, generally the Soviet Union and the countries of the Warsaw Pact. The terms Communist Bloc and Soviet Bloc were also used to denote groupings of states aligned with the Soviet Union, although these terms might include states outside Central and Eastern Europe.

In 1922, the RSFSR, the Ukrainian SSR, the Byelorussian SSR and the Transcaucasian SFSR, approved the Treaty of Creation of the USSR and the Declaration of the Creation of the USSR, forming the Soviet Union. Soviet leader Joseph Stalin, who viewed the Soviet Union as a "socialist island", stated that the Soviet Union must see that "the present capitalist encirclement is replaced by a socialist encirclement."

In 1939, the USSR entered into the Molotov–Ribbentrop Pact with Nazi Germany that contained a secret protocol that divided Romania, Poland, Lithuania, Estonia and Finland into German and Soviet spheres of influence. Eastern Poland, Latvia, Estonia, Finland and Bessarabia in northern Romania were recognized as parts of the Soviet sphere of influence. Lithuania was added in a second secret protocol in September 1939.

The Soviet Union had invaded the portions of eastern Poland assigned to it by the Molotov–Ribbentrop Pact two weeks after the German invasion of western Poland, followed by co-ordination with German forces in Poland. During the Occupation of East Poland by the Soviet Union, the Soviets liquidated the Polish state, and a German-Soviet meeting addressed the future structure of the "Polish region." Soviet authorities immediately started a campaign of sovietization of the newly Soviet-annexed areas. Soviet authorities collectivized agriculture, and nationalized and redistributed private and state-owned Polish property.

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