Leningrad Oblast
On 30 November 1939, the Soviet Union waged the Winter War against Finland. With the Moscow Peace Treaty in 1940, the Soviet Union gained some territories, including the Karelian Isthmus. Their Karelian population was quickly evacuated to inner Finland and later replaced with people from other parts of the Soviet Union. A small part of the territory (the municipalities of Kanneljärvi, Koivisto and Rautu) was put into Leningrad Oblast. The rest was given to the Karelo-Finnish Soviet Socialist Republic.