Military history of Finland during World War II

The military history of Finland during World War II encompasses three major conflicts. The first two––the defensive Winter War in 1939–1940, and the Continuation War alongside the Axis Powers in 1941–1944––were waged against the Soviet Union. The third one, the Lapland War in 1944–1945, followed the signing of an armistice agreement with the Allied Powers, which stipulated expulsion of German forces from Finnish territory.

By the end of hostilities, Finland managed to defend its independence, but had to cede nearly 10% of its territory, including its second largest city, Viipuri, and pay out a large amount of war reparations to the Soviet Union. As a result of this territorial loss, all Finnish Karelians were evacuated from their homes, relocating to areas that remained within the borders of Finland.

In 1809, the Russian Empire conquered Finland from Sweden in the Finnish War. Finland entered a personal union with the Russian Empire as a grand duchy with extensive autonomy. During the period of Russian rule the country generally prospered. However, in the early 20th century Russia tightened its grip on Finland, causing widespread resentment. When revolution broke out in Russia in 1917, Finland declared independence. In 1918 the Finnish Civil War broke out between the generally right-wing government supporters and left-wing rebels. The war ended with the victory of the government forces, supported by Germany, and the expulsion of Russian troops.

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