Military occupations by the Soviet Union

During World War II, the Soviet Union occupied and annexed several countries allocated to it in the secret Molotov–Ribbentrop Pact of 1939. These included the eastern regions of Poland (incorporated into three 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).

Source: Wikipedia — Military occupations by the Soviet Union (CC BY-SA 4.0)