The Karelo-Finnish Soviet Socialist Republic (Karjalais-suomalainen sosialistinen neuvostotasavalta; Карело-Финская Советская Социалистическая Республика Karelo-Finskaya Sovietskaya Sotsialisticheskaya Respublika) was a short-lived republic that was a part of the former Soviet Union. The republic existed from 1940 until it was merged back into the Russian SFSR in 1956 (as the Karelian Autonomous Soviet Socialist Republic).
The Karelo-Finnish Soviet Socialist Republic was set up on March 31, 1940 by merging the KASSR with the Finnish Democratic Republic (created in territory ceded by Finland in the Winter War by the Moscow Peace Treaty, namely the Karelian Isthmus and Ladoga Karelia, including the cities of Viipuri and Sortavala). The entire Karelian population of the ceded areas, about 422,000 people, was evacuated to Finland (see Evacuation of Finnish Karelia), and the territories were settled by people from other parts of the Soviet Union.
In the ensuing "Continuation War", in 1941 Finland occupied and reannexed the territory. In 1944 the Soviet Union recaptured the area, which was recognized by Finland in the Moscow Armistice and Paris Peace Treaty. The Karelians were evacuated again. The Karelian Isthmus with Vyborg (Viipuri) was transferred from Karelo-Finnish SSR to the Leningrad Oblast, but Ladoga Karelia remained a part of the republic.
On July 16, 1956, the republic was incorporated into the Russian SFSR as the Karelian Autonomous Soviet Socialist Republic. It became the Republic of Karelia, a subdivision of the Russian Federation, on November 13, 1991.
The chairman of the Karelo-Finnish Supreme Soviet (1940-1956) was Finnish communist Otto Ville Kuusinen. In the republic there was also a separate Karelo-Finnish Communist Party led in the 1940s by G.N. Kupriyanov.
| Name | Entered office | Left office |
|---|---|---|
| Mark Vasilyevich Gorbachev | 31 March 1940 | 11 July 1940 |
| Otto Kuusinen | 11 July 1940 | 16 July 1956 |
| Name | Entered office | Left office |
|---|---|---|
| I. P. Babkin (acting) | 31 March 1940 | 1940 |
| Pavel Prokkonen | 1940 | February 1947 |
| Voldemar Virolainen | February 1947 | 24 February 1950 |
| Pavel Prokkonen | 1950 | 16 July 1956 |