The Winter War: History and Details of the Russo-Finnish War

The origins of the Winter War lay deep in the geopolitical convulsions that had reshaped Europe throughout 1939, as Adolf Hitler's aggressive expansion forced Stalin to secure the Soviet Union's vulnerable northwestern frontier. The Molotov-Ribbentrop Pact signed in August 1939 had secretly divided Eastern Europe between Nazi Germany and the Soviet Union, placing Finland within the Soviet sphere of influence while giving Stalin a free hand to address what he perceived as serious security threats along the USSR's extended border with the capitalist world. From the Soviet perspective, Finland's independence represented an intolerable strategic vulnerability that allowed potential enemies to approach Leningrad within artillery range.

The security concerns that drove Soviet policy toward Finland reflected genuine strategic anxieties rooted in Russia's historical experience of invasion from the west. Leningrad, the USSR's second-largest city and crucial industrial center, lay only thirty-two kilometers from the Finnish border, making it vulnerable to attack from Finnish territory in the event of a broader European war. The naval bases that Germany had established in Finland during World War I demonstrated how easily a hostile power could use Finnish territory to threaten vital Soviet interests, while the recent fall of Poland showed how quickly small nations could be overrun by modern military forces.