Background of the Winter War

The background of the Winter War covers the period before the outbreak of the Winter War between Finland and the Soviet Union in 1939–1940, stretching from Finland's Declaration of Independence in 1917 to the Soviet-Finnish negotiations in 1938–1939. Before its independence, Finland was an autonomous grand duchy inside Imperial Russia. During the ensuing Finnish Civil War, the Red Guards, supported by the Russian Bolsheviks, were defeated. Fearful of Soviet designs, during the 1920s and 1930s, the Finns were constantly attempting to align themselves with Scandinavian neutrality, particularly with regard to Sweden. Furthermore, the Finns engaged in secret military co-operation with Estonia in the 1930s.

While during the late 1920s and early 1930s relations with the Soviet Union became normalized to a degree, from 1938 on, the Soviets, anxious that Finland could be used as a springboard for an invasion, started negotiations to conclude a military agreement. At the same time, Soviet leader Joseph Stalin's desire to recover the territories of Tsarist Russia lost during the chaos of the October Revolution and the Russian Civil War made Finland an obvious target. Due to the nature of Soviet demands, which included the installation of Soviet military facilities on Finnish soil, these negotiations went nowhere.

In August 1939, the Soviet Union and Nazi Germany signed the Molotov–Ribbentrop Pact, in which Eastern European countries were divided into spheres of interest; Finland belonged to the Soviet sphere of interest. In October 1939, Stalin gained control of the Baltic states and turned his sights on Finland, confident that control could be gained without great effort. The Soviet Union demanded territories on the Karelian Isthmus, the islands of the Gulf of Finland and a military base near the Finnish capital Helsinki, similar to the demands presented in the previous years. The Finns again refused, and the Red Army attacked on 30 November 1939. Simultaneously, Stalin set up a puppet government for the Finnish Democratic Republic, headed by the Finnish communist Otto Wille Kuusinen.

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