Soviet occupation

During World War II, the Soviet Union occupied and annexed several countries effectively handed over by Nazi Germany in the secret protocol Molotov–Ribbentrop Pact of 1939. These included Eastern Poland (incorporated into two different SSRs), as well as Latvia (became Latvian SSR),Estonia (became Estonian SSR),Lithuania (became Lithuanian SSR), part of eastern Finland (became Karelo-Finnish SSR) and eastern Romania (became the Moldavian SSR and part of Ukrainian SSR). Apart from Molotov–Ribbentrop Pact and post-war division of Germany, USSR also occupied and annexed Carpathian Ruthenia from Czechoslovakia in 1945 (became part of Ukrainian SSR).

Below is a lists of various forms of military occupations by the Soviet Union resulting from both, the Soviet pact with Nazi Germany (ahead of World War II), and ensuing Cold War in the aftermath of Allied victory over Germany.

Poland was the first country to be occupied by the Soviet Union during the World War II. The secret protocol of the Molotov-Ribbentrop pact stipulated Poland to be split between Soviet Union and Nazi Germany. In 1939, the total area of Polish territories occupied by the Soviet Union (including the area given to Lithuania and annexed in 1940 during the formation of Lithuanian SSR), was 201,015 square kilometres, with a population of 13.299 million, of which 5.274 million were ethnic Poles and 1.109 million were Jews.

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