The Soviet-Finnish War of 1939–1940, which lasted 103 days and is commonly known as the "Winter War," had its origins in the Nazi-Soviet Pact of August 23, 1939. The secret protocols of that non-aggression accord divided Eastern Europe into German and Soviet security zones. Finland, which had been part of the Russian Empire for more than a century prior to gaining its independence during the Russian Revolution, was included by that agreement within the Soviet sphere. Shortly after the dismemberment of Poland by Germany and the USSR, the Soviet government in October demanded from Finland most of the Karelian Isthmus north of Leningrad, a naval base at the mouth of the Gulf of Finland, and additional land west of Murmansk along the Barents Sea. The USSR offered other, less strategically important, borderland as compensation. After Finnish President Kiosti Kallio rejected the proposal, the Red Army, on November 30, invaded along the extent of their border as the Soviet Air Force bombed the Finnish capital, Helsinki.
Finland's most formidable defenses were a line of hundreds of concrete pillboxes, bunkers, and underground shelters, protected by anti-tank obstacles and barbed wire, which stretched across the Karelian Isthmus. General (and later Field Marshal) Carl Gustaf Mannerheim, a former tsarist officer, had organized these defenses, and he commanded Finland's armed forces during the war. During the first two months of conflict, Finland astonished the rest of the world by defeating the much larger and more heavily armed Soviet forces, especially along the Mannerheim Line. In snow—at times five to six feet deep—with temperatures plunging to -49° F,
the Finnish defenders were clad in white-padded uniforms, and some attacked on skis. The Red Army troops were entirely unprepared for winter combat. In early February, the USSR enlarged its forces to 1.2 million men (against a Finnish army of 200,000) and increased the number of tanks and aircraft to 1,500 and 3,000, respectively. In March the Red Army broke through the Mannerheim Line and advanced toward Helsinki. Finland was compelled to accept peace terms, which were signed in Moscow on March 12, 1940. The USSR acquired more territory than it had demanded before the war, including the entire northern coastline of Lake Ladoga and parts of southwestern and western Finland. Approximately 420,000 Finns fled from the 25,000 square miles of annexed territories.
Soviet victory, however, came at a very high cost. Whereas Finland lost about 25,000 killed in the war, Soviet Commissar of Foreign Affairs Vyacheslav Molotov acknowledged that immediately after the war almost 49,000 Soviet troops had perished. In 1993 declassified Soviet military archives revealed that 127,000 Soviet combatants had been killed or gone missing in action. The Red Army overwhelmed Finnish defenses with massive formations. For example, to take one particular hill, the USSR attacked its thirty-two Finnish defenders with four thousand men; more than four hundred of the Soviet assault troops were killed. Material losses were similarly lopsided in the war. Altogether, the Soviet Air Force lost about one thousand aircraft; Finland around one hundred.
The world's attention was focused on the Soviet-Finnish War, because at that time despite British and French declarations of war against Germany in September 1939 over Germany's invasion of Poland, there was no other fighting taking place in Europe. Finland was much admired in the democratic West for its courageous stand against a much larger foe, but to Finland's disappointment, that admiration did not translate into significant outside assistance. By contrast, Soviet aggression was widely condemned, and the USSR was expelled from the League of Nations. More importantly, Soviet military weakness was exposed, which served to embolden Hitler and confirm his belief that Germany could easily defeat the USSR.
Defeated Finland became increasingly worried when in the summer of 1940 the USSR occupied Estonia, which lay just forty miles across the Baltic Sea. Finland found a champion for its defense and a means to regain the lost territories when Germany attacked the Soviet Union in Operation Barbarossa on June 22, 1941. The USSR provided a convenient pretext for the start of the "Continuation War" (as the resumed hostilities are known in Finland), when it bombed several Finnish cities, including Helsinki, on June 25. While the Red Army retreated before the Nazi blitz to within three miles of Leningrad and twenty of Moscow, Finland invaded southward along both sides of Lake Ladoga down to the 1939 boundary. During the nearly nine hundred day siege of Leningrad, Finnish forces sealed off access to the city from the north. Close to one million Leningraders perished in the ordeal, primarily from hunger and cold in the winter of 1941–1942. Finland, which relied heavily on German imports during the war, rebuffed a Soviet attempt through neutral Sweden in December 1941 to secure a separate peace and relief for Leningrad. At the same time, the Finnish government refused German requests to attempt to cross the Svir River in force to link up with the Wehrmacht along the southeastern side of Ladoga. The lake remained Leningrad's only surface link with the rest of the USSR during the siege.
Finland's position in southern Karelia became increasingly vulnerable as its ally Germany began to lose the war in the USSR in 1943. In late February 1944, a month after the Red Army smashed the German blockade south of Leningrad, the Soviet Air Force flew hundreds of sorties against Helsinki and published an ultimatum for peace, which included, among other things, internment of German troops in northern Finland and demobilization of the Finnish Army. After Finland refused the harsh terms, the Red Army launched a massive offensive north of Leningrad on June 9. In early August Mannerheim managed to shore up Finnish defenses near the 1940 border at the same time that the Finnish parliament appointed him the country's president. However, continued German defeats and Soviet reoccupation of Estonia convinced President Mannerheim to agree to an armistice on September 19. The agreement restored the 1940 boundary, forced German troops out of Finland, leased to the USSR territory for a military base a few miles from Helsinki (which was later returned), and saddled Finland with heavy reparations. Although the Soviet Union basically controlled Finnish foreign policy until the Soviet collapse in 1991, of all of Nazi Germany's wartime European allies, only Finland avoided Soviet occupation after the war and preserved its own elected government and market economy.
See also: finland; finns and karelians; nazi-soviet pact of 1939; world war ii
Mannerheim, Carl. (1954). Memoirs. New York: Dutton.
Trotter, William R. (1991). A Frozen Hell: The Russo-Finnish Winter War of 1939–1940. Chapel Hill, NC: Algonquin Books of Chapel Hill.
Richard H. Bidlack