Under increasing pressure from both the United States and the Soviet Union, Finland finally declares war on former partner Germany.

As tension increased between Germany and the USSR, Finland saw in Hitler a possible ally in gaining back its territory. German troops were allowed on Finnish soil as the German prepared for their invasion of the Soviet Union, a war that the Finns joined. Finnish troops captured large areas of East Karelia back from the Soviet Union, they were reluctant to trespass the old borders of 1939 and help Germany in the siege of Leningrad.

The final act of capitulation came on March 3, 1945, with a formal declaration of war against the already dying Germany.