Answer:
The Winter War was a war between Finland and the Soviet Union from November 30, 1939 to March 13, 1940, when the Soviet Union began the Winter War by attacking without a declaration of war. The war is known for particularly difficult winter conditions (the winter of 1939–1940 was the coldest of the century), the huge loss of men of the Red Army, the motto tactics of the Finns and the “spirit of the Winter War”. As a result of the war, Finland lost 11 percent of its land to the Soviet Union and Vyborg, its second largest city.