This informative study explores the Soviet invasion of Finland, detailing the events of the Winter War of November 1939 to March 1940. The invasion was expected to be swift and decisive, however, the fighting qualities of the Finnish Army blunted the Soviet advance and inflicted high numbers of casualties. A combination of difficulties caused by the weather, the terrain, the Mannerheim Line defenses and Finnish tactics resulted in a fascinating David vs Goliath type struggle.