Finnish–Soviet war

Finnish–Soviet war, also known as the ‘Winter War’, was a direct consequence of the Nazi–Soviet Pact of August 1939 which assigned Finland to the Soviet sphere of influence. On 5 October Finland was requested to send a delegation to Moscow and between 12 October and 9 November three rounds of talks were held with Stalin and Molotov. Stalin wanted to strengthen the defences against an attacker coming through Finland by moving the frontier on the Karelian isthmus some 70 km. (43.5 mi.) further from Leningrad, and against a naval attack through the Gulf of Finland by taking Finnish islands in the gulf and leasing the port of Hanko for 30 years as a military base to close the entrance to the gulf. He also wanted frontier rectifications on the Arctic Ocean to strengthen the defences of Murmansk and in return offered Finland territorial compensation in Soviet Karelia.

Finland had secured independence after 1917 and experienced a civil war between Reds and Whites in which the Bolsheviks had assisted the defeated Reds. The basis of Finland's foreign policy was that the USSR was an implacable enemy which sought to reverse that defeat and that any significant concession to Soviet demands would encourage further encroachments on independence. Although Stalin showed a genuine readiness to bargain at the Moscow talks, Finland would not compromise. Stalin fell back on an alternative plan: the Leningrad military district would mount a full invasion of Finland. Serious resistance was not anticipated because Finnish workers would welcome the Soviets as liberators and refuse to fight: to encourage them a Finnish Peoples' government was formed by communist exiles led by O. W. Kuusinen to collaborate with the invasion.

After a contrived frontier incident at Mainila, on 26 November 1939, war began on 30 November with a general Soviet advance over the frontier and air raids on the interior (see Map 33). The Finnish Army of 1939 had ten divisions and some special units. It was inadequately equipped, short of automatic weapons despite its own Suomi machine pistol developed for forest warfare, had not received the planned heavy mortars, and had only 36 pre-1918 guns for each division. It was short of uniforms, tents, radios, and shells. But the soldiers had been trained intelligently to operate in forest terrain, in both summer and winter conditions, could move freely in the wilderness, using skis for mobility in snow, and were strongly motivated to defend Finland's recently-won independence against aggression. Further, the period of negotiation had allowed the Army to mobilize undisturbed and move into position. The frontier was some 1,000 km. (620 mi.) long but most of it trackless wilderness, impassable to a modern army. This allowed the Finnish commander, Marshal C. G. Mannerheim, to concentrate six divisions along the 65 km. (40 mi.) Mannerheim Line, a prepared system of defences which stretched across the Karelian isthmus. It consisted of field works reinforced at the most vulnerable points by 44 modern concrete bunkers, with automatic weapons but no anti-tank guns or artillery. Two divisions were posted between Lake Ladoga and Ilomantsi to protect the rear of the isthmus: the rest of the eastern frontier was crossed by a handful of poor roads, each guarded by special battalion-sized units. The strategic plan was to hold these positions long enough for outside assistance to arrive.

During the war, the Red Army used 26 divisions, comprising 1,200,000 men, lavishly equipped with motor transport and artillery and supported by 1,500 tanks and 3,000 aircraft. But communications and supply problems prevented the whole force being deployed at once. It was weakened by defective training and tactical leadership, partly a result of Stalin's purges, and was badly prepared for winter warfare, lacking white camouflage clothing, adequate anti-frost protection for equipment, and ski-troops for a campaign fought almost entirely in sub-arctic weather. On the isthmus General Meretskov commanded the Seventh Army with twelve divisions and a tank corps: north of Ladoga was the Eighth Army with six divisions, on its right the Ninth Army with five divisions, and, at Murmansk, the Fourteenth Army with three divisions. The Soviet superiority in manpower at the front was about 2 ½:1 and the plan was for a quick general advance on all fronts leading to the total occupation of Finland.

The Soviet advance up the Karelian isthmus ended in stalemate on the Mannerheim Line: despite repeated heavy assaults it remained intact everywhere and the Finnish reserves were not drawn in. Soviet material superiority was of no avail: Soviet aircraft could inhibit Finnish movements by day, but the hours of daylight were few, and their long-distance attacks on towns and communications, against light defences, caused little strategic damage and cost more than 800 aircraft destroyed. The tanks were potentially dangerous to the Finnish infantry who had no experience of armoured warfare and little proper anti-tank equipment. But after some early panics they improvised weapons, notably the Molotov cocktail which was very effective, as the tanks tended to operate in isolation from their infantry and could be hunted down after dark. The Soviet infantry used mass-assault tactics that ended in heavy losses.

After 27 December the Soviet forces broke off action on the isthmus. North of Lake Ladoga the Soviet deployment had been larger than the Finns had anticipated and Mannerheim had to use part of his strategic reserve to stabilize the front which, by 9 December, he managed to do. But on the three crossing-points on the eastern frontier improvement of communications on the Soviet side enabled them to advance in divisional strength and more of the Finnish reserve was needed to halt them; while the Murmansk troops easily overran the Petsamo area, cutting Finland off from the Arctic Ocean, but did not penetrate further south.

As soon as hostilities began a new government was formed in Finland to seek peace but the Soviet Union rejected all approaches on the grounds that it only recognized Kuusinen's Peoples' government, now established on Finnish soil at Terijoki. Finland appealed to the League of Nations for help: the USSR was expelled and all League members urged to support Finland. Since Germany sympathized with the Soviet Union all aid, whether equipment or volunteers, had to reach Finland through Norwegian ports. This caused such delays that almost no volunteers got into action and much matériel remained in Norway. Only Sweden, by straining the limits of neutrality, was able to supply substantial quantities of weapons and two battalions of volunteers in time to be used in the fighting. This meant that the value of the foreign aid to Finland was as much moral as material.

From late December, the Finns counter-attacked along the Eastern Front: facing road-bound Soviet columns, they moved ski troops through the forests to outflank and cut off the invading forces which were split up into isolated hedgehog positions which could be worn down individually. Spectacular victories were secured by Colonel P. Talvela at Tolvajärvi where, by 24 December, the Soviet 139th and 75th divisions were destroyed, and by Colonel H. Siilasvuo at Suomussalmi, where by 5 January he had destroyed the 163rd and 44th divisions: all the heavy equipment was captured and then used by the Finnish Army. But although the Soviet advance on the Eastern Front was halted for the duration of the war, surviving hedgehog positions could not be eliminated and these tied down substantial Finnish forces. Further, these spectacular tactical successes deluded even the Finnish leadership into thinking that the war was winnable, whereas strategically their effect was marginal. But politically they forced a change in Soviet policy, for in January the Soviet leaders signalled a willingness to negotiate with the government in Helsinki and tacitly to abandon the Kuusinen government. Contact between the two sides were continuous after 29 January, but the Finns felt strong enough to bargain. They were encouraged when, on 5 February, France and the UK approved a plan to send an expedition to Scandinavia, ostensibly to help Finland, in reality to seize the Swedish iron-ore mines (see also raw materials) and open a Second Front against Germany in Scandinavia: but to do this they needed a request for assistance from Finland.

Militarily the Soviet command was reorganized: General S. K. Timoshenko took command of a North-West Front: the Seventh Army was reinforced by a new Thirteenth Army of nine divisions and an armoured brigade. Intensive training was implemented to develop close co-operation of infantry, armour, artillery, and aircraft. On 1 February a fresh assault on the Mannerheim Line began: the defences were subjected to continuous bombardment, followed by combined infantry and armoured probes with close air support. The line broke at Summa on 11 February, the decisive factors being the sheer physical exhaustion of the defenders and shortages of ammunition for their artillery. Finnish counter-attacks failed to restore it and on 15 February the Finns retreated to an intermediate position of field works, wire, and tank obstacles, prepared since the outbreak of war. Soviet forces began to threaten this position by 18 February and after a pause for regrouping, broke it on 25 February. There remained a rear position, anchored on Viipuri: Soviet forces began to attack it on 3 March, and also launched troops and tanks over the sea-ice west of Viipuri (Vyborg), which secured a threatening bridgehead behind the line. When fighting ceased, the rear position had been penetrated and only a major strategic retreat could have won a respite for the Finns. On 9 March, Mannerheim advised the government to make peace.

Soviet terms were defined on 23 February: in addition to Hanko, the whole Karelian isthmus, including Viipuri and the north shore of Ladoga were demanded: the Petsamo area would be restored to Finland. The Finnish government procrastinated while it sought military intervention by Sweden, which was refused, and it then explored the Anglo-French offer to intervene, but judged it insufficient. A delegation flew to Moscow and signed the treaty of Moscow on 12 March 1940. Hostilities ceased the following day. Finland made peace because the war was lost without substantial outside assistance. The Soviet reason for making peace, when total victory was in reach, can only be surmised. Probably Stalin wanted freedom of manoeuvre for forthcoming developments in the European war and was nervous about Anglo-French intentions.

The USSR lost 200,000 dead and much matériel, but the worst loss was international credibility. World opinion overlooked the final successes and generally underrated Soviet military capacity. Further, in May 1940, the Supreme Military Soviet ordered a general reorganization of the forces in the light of wartime experience, which paid off in 1941. Finland lost 25,000 dead, a tenth of its territory and had to absorb 400,000 refugees.

The national will to survive enabled Finland to sustain these burdens and by June 1941 it had built a new, sixteen-division army, with adequate modern equipment. Germany provided much of the equipment because Hitler's plans to conquer the USSR assumed that Finland would co-operate. The Finns reacted positively to Hitler's covert approaches and in June 1941, in what was known as a continuation of the Winter War, mobilized for their own war of revenge, while in Lapland four German divisions were ready to attack Murmansk. This operation failed, but the Finnish Army regained the lost territories and advanced into Soviet Karelia to the line of Lake Onega and the River Svir. They stopped there and remained on the defensive into 1944.

Finland had joined the German attack on the USSR (see BARBAROSSA) in expectation of total German victory: after Stalingrad its leaders realized this would not happen and sought to withdraw from the war. But intermittent negotiations broke down in February 1944 and the USSR decided to force Finland to surrender. On 9 June 1944 a massive offensive on the isthmus achieved an immediate breakthrough and drove the Finns back beyond Viipuri: Mannerheim was compelled to abandon the Onega–Svir positions: emergency help had to be purchased from Germany by an undertaking not to make a separate peace and the front was stabilized in early August, roughly on the line of the 1940 frontier. The Soviet command needed resources for other fronts and allowed Finland to renege on the promise to Germany and conclude the armistice of 19 September 1944. This restored the 1940 frontier, substituted Porkkala for Hanko as the Soviet base and imposed heavy reparations on Finland. At that price Finland, alone among Germany's eastern partners, saved herself from Soviet occupation and survived the war with its sovereignty and western democratic society intact.

Anthony Upton

Bibliography

Mannerheim, C. G. , The Memoirs of Marshal Mannerheim (London, 1953).
Tanner, V. , The Winter War (London, 1957).
Upton, A. F. , Finland 1939–40 (London, 1974).