The ‘Winter War’ of 1939-1940, also known as the Russo-Finnish War, saw the tiny Finnish Army take on the might of the Soviet Union’s gigantic Red Army.

There was mistrust between the two countries. Finland believed the Soviet Union wanted to expand into its territory and the Soviet Union feared Finland would allow itself to be used as a base from which enemies could attack.

Finland declared itself neutral at the start of the Second World War, but the Soviet Union demanded concessions. Finland delayed, using the time to mobilise its army and seek help from Sweden and the Western Allies, including Britain and France, but with little success.

A faked border incident gave the Soviet Union the excuse to invade on 30 November 1939. The Red Army was ill-equipped, poorly led, and unable to deal with the Finnish terrain and winter weather. Though small and under-resourced, the Finnish Army was resilient, well-led and was able to use knowledge of the terrain to good effect.


The Soviet-Finnish War (Winter War)

A Finnish ski patrol, lying in the snow on the outskirts of a wood in northern Finland, on the alert for Soviet troops, 12 January 1940. 


Despite the overwhelming odds, Finland resisted for three months with little outside assistance. However, it was only a matter of time before the balance of power tipped in the Soviet Union’s favour.

The Red Army came back strongly. Their command structure was reorganised, modern equipment was brought in and there was a badly needed change of tactics and personnel.

Weapons and ammunition

'Molotov Cocktail' incendiary grenade

The Finns held Soviet Foreign Minister Vyacheslav Molotov responsible for the outbreak of the Russo-Finnish War and named an improvised incendiary grenade after him. The 'Molotov Cocktail' proved to be a primitive but effective anti-tank weapon against Soviet forces.

By early February 1940, the Finnish Army was exhausted and their defensive lines eventually overrun. Outside help never materialised. Finland was forced to sign the Treaty of Moscow on 12 March 1940, which ceded 11 per cent of its territory to the Soviet Union.

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