On 30 November 1939, the Soviet Union attacked Finland, beginning the conflict known as the Winter War. A small nation of four million faced one of the largest armies in the world.
Through a terrible winter of fighting, Finland's defenders turned the war into a legendary struggle for independence.
The outbreak of war
In the autumn of 1939, as the Second World War engulfed Poland, the Soviet Union demanded territorial concessions from Finland, including bases and the moving of the border on the Karelian Isthmus. Finland refused.
When negotiations broke down, the Soviet Union attacked without a declaration of war. Finnish forces were heavily outnumbered and outgunned, but they held a line of fortifications and knew the land they defended.
The first blows
Soviet forces struck along several axes, expecting a quick victory. Instead, they met fierce Finnish resistance. The famous 'Molotov cocktail' took its name from this very war, where Finnish soldiers used it against enemy armour.
The defence of Finland
Finland's strategy relied on mobility, winter skill and knowledge of the terrain. Finnish ski troops moved silently through the forests, cut enemy columns on the roads and used the cold as an ally.
- The Battle of Tolvajärvi in December 1939 was a major early Finnish victory.
- Finland's resistance stopped the Soviet advance on the Isthmus at the Mannerheim Line.
- The legendary 'motti' tactic surrounded and trapped isolated Soviet columns.
Against enormous odds, the defenders held through the hardest months, turning the war into a grinding stalemate that surprised the world.
The world looks on
Finland's struggle inspired sympathy and admiration across the world. Volunteers from many countries offered their help, and Sweden sent material aid and volunteers while remaining officially neutral.
The Soviet Union was expelled from the League of Nations over its invasion, but practical military help for Finland remained limited, and the war was decided in the north.
The Moscow Peace
In March 1940, with the war on the Isthmus turning against them and foreign help not arriving in time, Finland agreed to make peace. The Moscow Peace Treaty ceded parts of Karelia and the islands to the Soviet Union.
The Winter War had been a costly victory of resistance. Finland had preserved its independence and shown the world its determination, but at a heavy price in lives, territory and a remnant of bitterness that would shape the years to come.
Frequently asked questions
When was the Winter War fought?
It ran from 30 November 1939 to 13 March 1940, lasting just over three months.
Who won the Winter War?
The Soviet Union won in the sense that Finland agreed to territorial concessions, but Finland preserved its independence, which was its central goal.
What were the consequences for Finland?
Finland lost parts of Karelia and several islands but kept its independence, and the war strengthened its national unity and determination.
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