|Date:||30 November 1939 – 13 March 1940|
|Territory:||Moscow Peace Treaty|
|Commander1:||Carl Gustaf Emil Mannerheim|
|Commander2:||Kliment Voroshilov |
130 aircraft 
|Strength2:||1,000,000 men |
3,880 aircraft 
|Casualties1:||26,662 dead |
|Casualties2:||126,875 dead or missing |
The Winter War (Finnish: talvisota, Russian: ''Зимняя война'', Swedish: vinterkriget) or the Soviet-Finnish War (Russian: Советско-финская война) began when the Soviet Union attacked Finland on 30 November 1939, three months after the invasion of Poland by Germany that started World War II. Because the attack was judged as illegal, the Soviet Union was expelled from the League of Nations on 14 December.
The Soviet forces had four times as many soldiers as the Finns, 30 times as many aircraft and 218 times as many tanks. However, the Red Army had recently been subjected to a drastic purge in 1937 that crippled it, reducing its morale and efficiency shortly before the outbreak of hostilities. With up to 50% of army officers executed, including the vast majority of those of the highest rank, the Red Army in 1939 had many inexperienced senior officers. Due to a combination of these factors, and an extremely high commitment and morale in the Finnish forces, the Finns were able to resist the invasion of their country with great success and for far longer than the Soviets had expected.
Finland held out until March 1940, when it signed the Moscow Peace Treaty, ceding about 9% of its pre-war territory and 20% of its industrial capacity to the Soviet Union. Soviet losses on the front were large, and the country's international standing suffered. Also, the fighting ability of the Red Army was questioned, a factor that contributed to Adolf Hitler's decision to launch Operation Barbarossa. Finally, the Soviet forces did not accomplish their primary objective of conquest of Finland but gained only a slice of territory along Lake Ladoga. The Finns retained their sovereignty and gained considerable international goodwill.
The 12 March peace treaty thwarted a half-hearted Franco-British plan to send troops to Finland through northern Scandinavia (the Allied campaign in Norway). One of the Allied operation's major goals was to take control of northern Sweden's iron ore and cut deliveries to Germany.
Finland had long been the eastern part of the Swedish kingdom when Imperial Russia conquered it in 1809 during the Napoleonic Wars, converting it to an autonomous buffer state in the Russian Empire to protect Saint Petersburg, the imperial capital.
Western Karelia's history is different from the rest of Finland's history. Most of the area paid tribute to the Russian Republic of Novgorod, and was the arena of Swedish-Novgorodian Wars. The southwestern area, from the River Sestra to the River Vuoksi and Lake Saimaa (including Viborg) was annexed by Sweden at the same time as the rest of Finland, and the border, between Sweden and Novgorod, was defined by the Treaty of Nöteborg, in 1323. In 1617 (when Russia was still recovering from the Time of Troubles), Sweden captured the remainder of Western Karelia. During the Swedish sovereignty this region lost all of its Russian ecclesiastical and bourgeois inhabitants and much of its Russian Orthodox Karelian population, with much of it moving to the Tver region. Sweden lost the Karelian isthmus and the Ladoga Karelia in 1721 to Russia as a result of the Great Northern War. In 1743 Sweden ceded control of southern Karelia to Russia as a result of the Russo-Swedish War (1741–1743). In 1812, Russian Tsar Alexander I incorporated this region (known as Old Finland or Viipuri Province in Finland) into the Grand Duchy of Finland.
The 19th century saw the Fennoman movement, Finland's language strife and the publication of the Finnish national epic Kalevala. Finnish nationalism was born. At the turn of the century the Russian Empire attempted to strengthen central government and unify itself by means of Russification. The abortive assimilation of Finland soured relations and increased support for movements vying for self-determination.
Following the October Revolution that brought the Communists to power in Russia, rights of self-determination were declared by Bolsheviks as one of founding stones of the "new order". Taking advantage of the Bolsheviks' standing, Finland declared itself independent on 6 December 1917. In the subsequent Finnish Civil War, German-trained Finnish Jäger troops and regular German troops played a crucial role. Only Germany's defeat in World War I prevented the establishment of a Germany-dependent monarchy under Frederick Charles of Hesse as King of Finland.
Following the war, German - Finnish ties remained close, thanks to the German role in Finnish independence. When the National Socialists rose to power, however, relations chilled as few Finns sympathised with National Socialism. Even the clandestine military co-operation in submarine building was allowed to lapse.
Instead, Finland turned to Western Europe and Scandinavia for co-operation. More Finnish officers were trained in France than in all other countries combined. Also, French officers were instrumental in designing the fortifications of the Mannerheim Line. Great Britain was the largest trading partner, and Sweden was easily accessed through the same language, as native Swedish speakers were abundant amongst the Finnish political and cultural elite.
The relationship between the Soviet Union and Finland had been tense - the two periods of forced Russification at the turn of the century and the legacy of the failed Soviet-backed socialist rebellion in Finland, along with two Finnish military expeditions (the Viena expedition in 1918 and the Aunus expedition of 1919), when Finnish volunteers tried to take Russian East Karelia, which had never been a part of the Swedish-Finnish state or the Great Duchy of Finland even though populated with Fenno-Ugric tribes, contributed to a strong mutual distrust. Stalin feared that Nazi Germany would eventually attack, and with the Soviet-Finnish border in the Karelian Isthmus just 32 kilometres (20 miles) away from Leningrad, Finnish territory would have provided an excellent base for the attack. In 1932, the Soviet Union signed a non-aggression pact with Finland. The agreement was re-affirmed in 1934 for ten years. However, the Soviet Union violated the Treaty of Tartu in 1937, by blockading Finnish merchant ships navigating between Lake Ladoga and the Gulf of Finland.
In April 1938, or possibly earlier, the Soviet Union began diplomatic negotiations with Finland, trying to improve their mutual defence against Germany. The Soviets were mainly concerned that Germany or France and Great Britain would use Finland as a bridgehead for an attack on Leningrad, and demanded a territorial swap to move the border farther away from the city. More than a year passed, with little progress, and the political situation in Europe worsened.
The Soviet Union and Nazi Germany signed a mutual non-aggression pact, the Molotov-Ribbentrop Pact, on 23 August 1939. The pact also included a secret clause allocating the countries of Eastern Europe between the two signatories. Finland was consigned to the Soviet "sphere of influence". The German attack on Poland on 1 September was followed by the Soviet invasion of Poland from the east. Within a few weeks, they had divided the country between them.
In the autumn of 1939, the Soviet Union demanded that Finland agree to move the border 25 kilometres (16 miles) back from Leningrad. It also demanded that Finland lease the Hanko Peninsula to the USSR for 30 years for the creation of a naval base there. In exchange, the Soviet Union offered Finland a large part of Karelia (more than twice the size). This offer was referred to in Finland as "two pounds of dirt for one pound of gold".
The Finnish government refused the Soviet demands. The Soviet General Staff under Boris Shaposhnikov and Alexander Vasilevsky was already drawing up plans for an offensive. On 26 November, the Soviets staged the shelling of Mainila, an incident in which Soviet artillery shelled areas near the Russian village of Mainila, then announced that a Finnish artillery attack had killed Soviet troops. The Soviet Union demanded that the Finns apologize for the incident and move their forces 20–25 kilometres from the border. The Finns denied any responsibility for the attack and rejected the demands, which the Soviet Union then used as an excuse to withdraw from the non-aggression pact. On 30 November, Soviet forces invaded Finland with 27 divisions, totalling 630,000 men, bombed civilian boroughs of Helsinki and quickly reached the Mannerheim Line.
The Terijoki Government, a Soviet puppet regime created in the occupied Finnish border town of Terijoki (now Zelenogorsk) on 1 December 1939, was also called the Finnish Democratic Republic. It was headed by Otto Ville Kuusinen and was used for both diplomatic purposes (it was immediately recognized by the Soviet Union) and for military ones (they hoped it would encourage socialists in Finland's Army to defect). This republic was not particularly successful but lasted until 12 March 1940, and was eventually incorporated into the Russian Karelo-Finnish SSR on 31 March.
See also: Winter War Order of Battle.
Initially, Finland had a mobilized army of only 250,000 men, but these troops turned out to be fierce adversaries employing small-unit surrounding "motti" tactics, fast-moving ski troops in white camouflage suits, and local knowledge. Many had spent most of their lives in the forest; the vast majority of Finns were rural dwellers until the 1950s. The conditions of the winter of 1939–40 were harsh; temperatures of −40 °C (−40 °F) were not unusual, and the Finns were able to use this to their advantage. Often, they opted not to engage the enemy in conventional warfare, instead targeting field kitchens (which were crucial for survival in the cold weather) and picking off Soviet troops huddled around camp fires.
At the beginning of the war, only those Finnish soldiers who were in active service at the time had uniforms and weapons. The rest had to make do with their own clothing, which was their normal winter clothing in many instances, with a semblance of an insignia added. These mismatched "uniforms" were nicknamed "Model Cajander" after the Prime Minister Aimo Cajander. The Finns alleviated their shortages by making extensive use of equipment, weapons and ammunition captured from the enemy. The army had not changed the calibre of its weapons after independence and was able to use Soviet ammunition. The deployment of poorly trained and badly led Soviet troops gave the advantage to the Finns, allowing the latter ample opportunities to capture war booty. Though the Finns had few anti-tank weapons, they had the Molotov Cocktail, an improvised petrol bomb adapted from the Spanish Civil War, which was used with great success in destroying or disabling around 2,000 Soviet tanks. One Finnish soldier is quoted as saying: "I never knew a tank could burn for so long."
The Soviets attacked in regimental strength, with their dark uniforms easily visible against the white snow, so they were easily targeted by the Finns' snipers and machine guns. Corporal Simo Häyhä was credited with 542 confirmed kills, making him the deadliest sniper in military history. When the Red Army tried to use their own snipers, the Finns countered with the "Kylmä-Kalle" (Cold Kalle) tactic. A mannequin or other doll was dressed as a tempting target, such as an officer sloppily covering himself. Soviet snipers were usually unable to resist such a target. Once the Finns determined the angle from which the shot had come, a heavy-calibre anti-tank rifle, such as a "Norsupyssy" ("Elephant Gun") or Boys anti-tank rifle, was fired at the Soviet sniper to kill him.
Soviet inexperience, naivety, and lack of motivation were important factors in the Finnish success during the war. The attackers were not expecting much resistance; General Kirill Meretskov estimated it would take only 10 to 12 days for his 26 well-equipped 14,000-man divisions to reach Helsinki. Soviet soldiers had even been warned not to cross the border into Sweden by mistake. Their propaganda had been so convincing, that it was felt that the Finns would wave flags and welcome the Red Army with open arms.
Because of Stalin's purges, the commanders of the Red Army had suffered significant peacetime losses, including 3 of its 5 marshals, 220 of its 264 division-level commanders or higher, and 36,761 officers of all ranks; fewer than half of the officers remained in total. These were commonly replaced by people less competent but considered more "loyal" to their superiors, since Stalin had superseded his commanders with commissars or political officers. Tactics which were already obsolete by World War I were sometimes employed. Tactics were strictly "by the book", because failed initiative carried a high risk of execution. Many Soviet troops were lost because commanders refused to retreat; commissars did not allow them to do so and often executed commanders who disobeyed.
The Soviet army was poorly prepared for winter warfare, particularly in forests, and made heavy use of vulnerable motorized vehicles. These vehicles were kept running continuously, so their fuel would not freeze, which led to increased breakdowns and aggravated fuel shortages. Although the Red Army had modern medium tanks, it persisted at the outset in deploying older, more lightly-armoured models such as the T-26, which the Finns could put out of action with their .55-caliber (14mm) and 20mm anti-tank rifles, or the ubiquitous Molotov Cocktail. One of the most remarkable losses in military history is the so-called "Battle of Raate-Road", during the month-long Battle of Suomussalmi. The Soviet 163rd and the 44th Infantry Divisions comprising 25,000 troops were almost completely destroyed, after marching along the forest roads straight into an ambush. A small unit blocked the Soviet advance, while Finnish Colonel Hjalmar Siilasvuo and his 9th Division of 6,000 troops cut off the retreat route, split the enemy force into smaller fragments and then destroyed it in detail. The Soviet casualties amounted to up to 23,000 men, while the Finnish lost around 800 men. In addition, the Finnish troops captured 43 tanks, 71 field and anti-aircraft cannons, 29 anti-tank cannons, AFVs, tractors, 260 trucks, 1,170 horses, infantry weapons, ammunition, medical and communication material.
The Soviet commander, Vinogradov, and two of his chief officers survived the battle. When they reached the Soviet lines four days later, they were court martialled, found guilty and sentenced to death; the executions were carried out immediately. The charge was losing 55 field kitchens to the enemy.
Following this battle, on 7 January, for the disastrous failures, Kliment Voroshilov was replaced with Semyon Timoshenko as the commander of the Soviet forces in the war (and four months later as the People Commissar [Minister] of Defense as well).
The Soviets failed to take advantage of their numerical superiority at the start of the war. Finland massed 130,000 men and 500 guns in the Karelian Isthmus, the main theater of the war; the Soviets attacked with only 200,000 men and 900 guns. Their 1,000 tanks were ineffectively used and took massive losses.
At the start of hostilities, the Finnish Air Force had 146 aircraft of all types at its disposal. The primary fighter aircraft were 15 Bristol Bulldog IVs, which had entered service in 1935, and 41 of the more modern Fokker D.XXI. There were also 18 license-built Bristol Blenheim bombers. In 1939, an order had been placed in Italy for 25 Fiat G.50 fighters; two were being assembled in Sweden when the war broke out.
During the war, a number of aircraft were ordered from abroad:
In air combat, Finland used the "finger four" formation (four planes split into two pairs, one flying low and the other high, with each plane fighting independently of the others, yet supporting its wingman in combat), which was superior to the Russian tactic of three fighters flying in a delta formation. This formation and the credo of Finnish pilots to always attack, no matter the odds, contributed to the failure of Russian bombers to inflict substantial damage against Finnish positions and population centres.
The Winter War was also a naval war that went on until the Baltic Sea froze, as it usually does in winter, and made the movement of warships very difficult. On the water, it was a mostly one-sided affair. Although Stalin had purged all but one of the navy's admirals and over three thousand sailors, the Soviet Navy had the advantage in both the quantity of the leftovers from the Tsarist era as well as quality from a building program in the 1930s that had produced everything up to large cruisers. The Finnish Navy was weak in comparison. The most powerful units left from the Finnish civil war were two gunboats from 1917–18. In the inter-war years, a small number of new ships had been ordered. In the early 1930s, five submarines had joined the navy, as well as two well-armed but slow coastal defence ships with 254 mm guns as their main battery.
In addition to its navy, Finland had its coastal artillery batteries guarding important harbours and naval bases along its coast. Most batteries were leftovers from the Russian period, the 15.2 cm gun being the most numerous, but Finland had modernized its old guns and installed a number of new batteries, the largest a 305 mm gun battery originally intended to block the Gulf of Finland to Soviet ships with the help of batteries on the Estonian side.
Soviet warships attacked Finnish coastal batteries as long as the weather allowed. Sending light ships against even old coastal batteries had historically proved very dangerous; with nothing but a sunk destroyer and a number of damaged ships the Soviet Navy did not manage to influence the war.
The Coastal artillery had its greatest effect upon the land war. Batteries near the front were in well-protected fixed positions, with a higher rate of fire and greater accuracy than mobile artillery. Land batteries near the coast helped steady the defence of the Karelian Isthmus in conjunction with army artillery.
In March, as the Soviets had broken through the front, all reserves were thrown into the fighting near Viborg. The Soviets tried to cross the ice of the Gulf of Viipuri and come up behind the city, but the Finnish coastal artillery fired their heaviest guns, breaking the ice under the Russians and preventing a clean breakthrough.
The vast bulk of the Red Army's troops that fought in the Winter War were taken from the southern regions of the Soviet Union. It was Stalin's opinion that Soviet troops from the area immediately bordering Finland could not be trusted to fight against the Finns. These southern Red Army soldiers had no experience with Arctic winter conditions and virtually no forest survival skills. Not only were they up against the Finns who were experts in winter warfare and knew the land, but the weather during the war was one of the three worst winters in Finland in the 20th century.
To the surprise of both the Soviets and the Finnish conservatives, the majority of the Finnish socialists did not support the Soviet invasion, but fought alongside their compatriots against the common enemy. Many Finnish communists had moved to the Soviet Union in the 1930s to "build Socialism", only to end up victims of Stalin's Great Purges, which led to widespread disillusionment and even open hatred of the Soviet regime among socialists in Finland.
Another factor was the advancement of Finnish society and laws after the civil war that helped decrease the gap between different classes of society. This healing of the wounds and rifts of the Finnish Civil War (1918) and from Finland's language strife and the coming together of different factions of society is still referred to as "the Spirit of the Winter War". The Molotov-Ribbentrop Pact between the Soviet Union and Germany had shaken the world views of both the bourgeois as well as the working class Finns. Many Finns had believed that Germany would eventually intervene against the Soviet Union as Imperial Germany had in 1918. In similar fashion the ordinary workers had believed that the Soviet Union was a guarantee for peace and force against Nazi Germany. After the signing, Germany was in league with the Soviet Union against Finland. The workers had witnessed the Soviet Union invading Poland instead of fighting the Nazis. On the eve of war there was very little trust for any foreign power - be it socialist, German, the League of Nations or the western powers. Nonetheless, some communists were not allowed to fight in Finland's conscripted army because of their political background.
See also: Hungarian Volunteers in the Winter War. World opinion at large supported the Finnish cause. The World War had not yet begun in earnest and was known to the public as the Phony War; at that time, the Winter War was the only real fighting in Europe besides the German and Soviet invasion of Poland, and thus held major world interest. The Soviet aggression was generally deemed unjustified. Various foreign organizations sent material aid, such as medical supplies. Finnish immigrants in the United States and Canada returned home, and many volunteers (one of them future actor Christopher Lee) traveled to Finland to join Finland's forces: 1,010 Danes (including Christian Frederik von Schalburg, a captain in Christian X of Denmark's bodyguard and later commander of Frikorps Danmark, a volunteer unit created by Nazi Germany in Denmark during WWII), 8,700 Swedes, 725 Norwegians, 372 Ingrians, 346 Finnish expatriates, 366 Hungarians and 210 volunteers of other nationalities made it to Finland before the war was over. Foreign correspondents in Helsinki wrote, and even greatly exaggerated, reports of Finnish ingenuity and successes in combat.
As a fascist government, Italy had staunchly supported Franco in Spain fighting Republican communists and anarchists supported by the Soviet Union. Italy therefore promptly responded to requests by Finland for military assistance and equipment for use against the Soviet government. The Italian Air Force sent 35 Fiat G.50 fighters, while the Italian Army supplied 94,500 new M1938 7.35 mm rifles for use by Finnish infantry. Also a handful of men fought in the Winter War.
The Norwegian government did not allow officers or under-officers to volunteer to the war in Finland out of fear that that would aggravate the Germans (they wanted to remain neutral at all cost). Of the 725 Norwegians that volunteered to fight for Finland only 125 made to the relatively tranquil Salla front and that just three weeks before the war ended. None of the volunteers were killed or wounded. Many of the volunteers were unfit for fighting and many ended up in rest homes and institutions for alcoholics during their stay in Finland. Several of the future leaders of the Norwegian resistance movement such as Max Manus and Leif "Shetland" Larsen were among the volunteers. The most highly decorated Norwegian in the later resistance movement, "Kjakan" Sonsteby, spent his stay as an office clerk (like many of his countrymen in the Winter War). There were numerous nationwide collections campaigns of supplies and money in Norway to help the Finns.
An important venue for collections for Finland were sporting events, several of which were held to the benefit of Finland in Norway during the war. Some 50,000 backpacks filled with supplies were collected in Norway and dispatched to Finland. Collections of rifles (mostly Krag-Jørgensen models) and home knitted shooting gloves also took place. Sigrid Undset, Norwegian author and Nobel laureate, donated her Nobel medal to Finland on 25 January 1940.
The Norwegian government secretly donated the Finns 12 German-made 7.5 cm field gun m/01s (designated 75 K 01 in Finnish service) in February 1940.  Included in the covert artillery transfer were 12,000 shells. Norway also allowed the transfer of aircraft to Finland via Sola Air Station, near Stavanger.   Norwegian volunteers took part in the assembly of some of the aircraft at the Saab factory in Trollhättan, Sweden.
One of the main reasons that Franco-British plan, Operation Avon Head, to send troops to Finland never materialized was that Norway would not allow them to use their ports and territory for troops transfer. They explicitly threatened to gun down any ship that came near Trondheim or Narvik on that mission.
The North Norwegian county of Finnmark received over 1,000 Finnish refugees from Petsamo by 6 February 1940; as the Red Army advanced through that lightly defended area Finnish civilians sought shelter on the Norwegian side of the Pasvik/Paatsjoki River. Finnish soldiers of the independent Lapland Group that retreated across the border into Finnmark were transported south and interned at Hegra Fortress in the Nord-Trøndelag county of Central Norway. The internees were released and returned to Finland at the turn of the year 1939-1940.
See main article: Sweden and the Winter War. Sweden, which had declared itself to be a non-belligerent rather than a neutral country (as in the war between Nazi Germany and the Western Powers) contributed military supplies, cash, credits, humanitarian aid and some 8,700 Swedish volunteers prepared to fight for Finland. The Swedish Army, which had been downsizing its armed forces since the 1920s, sold large quantities of Swedish M96 6.5 mm rifles and surplus stocks of ammunition to Finland. Perhaps most significant was the Swedish Voluntary Air Force, in action from 7 January, with 12 Gloster Gladiator II fighters, five Hawker Hart bombers, and eight other planes, amounting to one third of all the Swedish Air Force's fighters at that time. Volunteer pilots and mechanics were drawn from the ranks. The renowned aviator Count Carl Gustav von Rosen, nephew of Carin Göring, Hermann Göring's first wife, volunteered independently. There was also a volunteer work force, of about 900 workers and engineers. In March the unit was to be reinforced with five Junkers Ju 86 bombers on the 11th of March the bombers were in the Swedish town of Boden with all preparations completed but the end of hostilities on the 13th precluded their deployment.
The Swedish Volunteer Corps with 8,402 men in Finland - the only common volunteers who had finished training before the war ended - began relieving five Finnish battalions at Märkäjärvi in mid-February. Together with three remaining Finnish battalions, the corps faced two Soviet divisions and were preparing for an attack by mid-March but were inhibited by the peace agreement. Thirty-three men died in action, among them the commander of the first relieving unit, Lieutenant Colonel Magnus Dyrssen.
The Swedish volunteers remain a source of dissonance between Swedes and Finns. The domestic debate in Finland had in the years immediately before the war given common Finns hope of considerably more support from Sweden, such as a large force of regular troops, that could have had a significant impact on the outcome of the war - or possibly caused the Russians not to attack at all.
However the help from volunteers, especially the Scandinavian ones, was appreciated by the Finns. This is shown by the fact that during the Norwegian Campaign against the German invasion in April 1940 a Finnish group of volunteers formed an ambulance unit and helped the defenders until forced to return home because of the success of the German armed forces. A group of Swedish and Finnish volunteers also fought alongside Norwegian soldiers against the German invaders near Os, on 2 May as well.
The British government sent the Finnish air force 30 Bristol Blenheim bombers. U.S.-made Brewster B239's, came too late to participate in combat missions, and the same applied to ten Hawker Hurricane I fighters. The British government also provided quantities of small arms and ammunition, including a large number of Boys anti-tank rifles in 1939 and 1940. The latter weapon was popular with the Finns, because it could penetrate the armor of Soviet T-26 tanks which they encountered in many engagements.
France also sent aircraft, including the Morane Saulnier M.S.406 fighter. In 1940, it was decided to send a new fighter, the Caudron-Renault C.714. Six C.714s previously marked for shipment to the Polish Air Force were placed in containers and diverted to Le Havre harbour for shipment to Finland. On 12 March 1940, the first six aircraft were already on their way to Finland when news of the armistice between Finland and the Soviet Union was received. At the time deliveries were halted, ten aircraft were in containers at Le Havre waiting to be lifted to the ships and three more were on their way from Paris. The French Army also supplied small arms and ammunition.
Within a month, the Soviet leadership began to consider abandoning the operation, and on 29 January 1940, via intermediaries in Sweden, Finland's government was approached on the subject of preliminary peace negotiations. Until this point, Finland had fought for its existence as an independent and democratic country. However, at the news that Finland might be forced to cede its territory or sovereignty, public opinion in France and Britain, already favorable to Finland, swung in favor of intervention. When rumors of an armistice reached governments in Paris and London, both decided to offer military support.
In February 1940, the Allies offered to help: the Allied plan, approved on 4–5 February by the Allied High Command, consisted of 100,000 British and 35,000 French troops that were to disembark at the Norwegian port of Narvik and support Finland via Sweden while securing supply routes along the way. Plans were made to launch the operation on 20 March under the condition that the Finns first make a formal request for assistance (this was done to avoid German charges that the Franco-British forces constituted an invading army). On 2 March, transit rights were officially requested from the governments of Norway and Sweden. It was hoped that Allied intervention would eventually bring the two still neutral Nordic countries, Norway and Sweden, to the Allied side by strengthening their positions against Germany - although Hitler had by December declared to the Swedish government that Western troops on Swedish soil would immediately provoke a German invasion.
However, only a small fraction of the Western troops were intended for Finland. Proposals to enter Finland directly, via the ice-free harbour of Petsamo, had been previously dismissed. There was speculation in some diplomatic quarters, encouraged by German sources, that the true objective of the operation was to occupy the Norwegian shipping harbour of Narvik and the vast mountainous areas of the north-Swedish iron ore fields, from which the Third Reich received a large share of its iron ore, critical to war production. If the governments of France and Britain later broke their pledge not to seize territory or assets in Norway and Sweden, and Franco-British troops later moved to halt exports to Germany, the area could become a significant battleground between the Allies and the Germans.
The Franco-British plan, as initially designed, proposed a defense of all of Scandinavia north of a line Stockholm - Gothenburg or Stockholm - Oslo, i.e. the British concept of the Lake line following the lakes of Mälaren, Hjälmaren, and Vänern, which would provide good natural defence some 1,700 - 1,900 kilometres (1,000-1,200 miles) south of Narvik. The expected frontier, the Lake line, involved not only Sweden's two largest cities, but could potentially result in large amounts of Swedish territory either occupied by a foreign army or located in a potential war zone. Later, the plan was revised to include only the northern half of Sweden and the rather narrow adjacent Norwegian coast. Despite this compromise, the Norwegian government denied transit rights to the proposed Franco-British expedition.
The Swedish government, headed by Prime Minister Per Albin Hansson, also declined to allow transit of armed troops through Swedish territory, in spite of the fact that Sweden had not declared itself neutral in the Winter War. Instead, the Swedish government made the curious argument that since it had declared a policy of neutrality in the war between France, Britain, and Germany, the granting of transit rights by Sweden to a Franco-British corps, even though it would not be used against Germany, was still an illegal departure from international laws on neutrality. This strict interpretation appears to have been merely a pretext to avoid angering the Soviet and Nazi German governments, as it was abandoned after only three months. On 18 June 1941, the Swedish government quickly agreed to Nazi Germany's demand to transit rights across Sweden for German troops on their way from the then occupied Norway to Finland, in order to join the German attack on Soviet union. A total of 2.14 million German soldiers, and more than 100,000 German military railway carriages, would cross neutral Swedish territory in a thunderous display of "might over right" for the next three years.
The Swedish Cabinet also decided to reject repeated pleas from the Finns for regular Swedish troops to be deployed in Finland, and in the end the Swedes also made it clear that their present support in arms and munitions could not be maintained for much longer. Diplomatically, Finland was squeezed between Allied hopes for a prolonged war and Swedish and Norwegian fears that the Allies and Germans might soon be fighting each other on Swedish and Norwegian terrain. In addition, Norway and Sweden feared an influx of Finnish refugees should Finland lose to the Soviets.
While Germany and Sweden pressured Finland to accept peace on bad conditions, Britain and France had the opposite objective. Different plans and figures were presented for the Finns. At the start, both France and Britain promised to send 20,000 men to arrive by the end of February. By the end of that month, Finland's Commander-in-Chief, Field Marshal Mannerheim, was pessimistic about the military situation. Therefore, on 29 February the government decided to start peace negotiations. That same day, the Soviets commenced an attack against Viipuri.
When France and Britain realized that Finland was considering a peace treaty, they gave a new offer of 50,000 troops, if Finland asked for help before 12 March. Through Soviet agents in the French and British governments, indications of Franco-British plans reached Stalin, and may have contributed heavily to his decision to increase military pressure on the Finnish Army, while at the same time offering to negotiate an armistice. Because of the Soviet Union's vast numbers of troops and reserves, it has been argued that without massive Allied intervention, nothing could have deterred the Soviet Union from conquering the entirety of Finland.
By the end of the winter, it became clear that the Finnish forces were becoming exhausted, and German representatives, not knowing that the negotiations were already ongoing, suggested that Finland should negotiate with the USSR. Soviet casualties had been high, and the situation was a source of political embarrassment for the Soviet regime. With the spring thaw approaching, the Russian forces risked becoming bogged down in the forests, and a draft of peace terms was presented to Finland on 12 February. Both the Germans and the Swedes were keen to see an end to the Winter War; the latter feared the collapse of its neighbor. As Finland's Cabinet hesitated in face of the harsh Soviet conditions, Sweden's King Gustaf V made a public statement, in which he confirmed having declined Finnish pleas for support from Swedish troops.
By the end of February, the Finns had depleted their ammunition supplies. Also, the Soviet Union had finally succeeded in breaking through the Mannerheim Line. On 29 February, the Finnish government agreed to start negotiations. By 5 March, the Soviet army had advanced 10 - 15 kilometres past the Mannerheim Line and had entered the suburbs of Viipuri. The Finns proposed an armistice on the same day, but the Soviets wanted to keep the pressure on and declined the offer the next day. Indeed, the fighting continued up to noon (Leningrad time), 13 March, half a day after the peace treaty was signed, according to the terms of the protocol.
After the war, the situation of the Finnish army at Karelian Isthmus at the end of the war had created significant discussion. The orders were already given to prepare a retreat to the next line of defence in the Taipale sector. The estimates of how long the enemy could have been held in these kinds of retreat-and-stand operations varied from a few days to a couple of months, most averaging around a few weeks.
It is speculated that Stalin had practically wiped out his intelligence apparatus during the purges, thus damaging the effectiveness of spies in Finland and other countries, as well as cowing operatives into writing the kind of reports they thought Stalin wanted to read. Thus he was not aware of the real situation in Finland and amongst the Western Allies. 
Soviet intelligence sources were informing their leadership of the Allied plans to intervene in the war, but not of the details or the actual unpreparedness of the Allies. Therefore, the Soviets felt forced to seek a premature end to the war before the Allies intervened and declared war on the Soviet Union.
During four months of fighting, the Soviet Army suffered huge losses. One Red Army General remarked that "we have won enough ground to bury our dead". Casualty estimates vary widely - from 48,000 killed, died from wounds, and missing in action, as quoted by Soviet officials immediately after the war, to 391,800 according to some recent research According to Nikita Khrushchev, 1.5 million men were sent to Finland and one million of them were killed, while 1,000 aircraft, 2,300 tanks and armored cars and an enormous amount of other war materials were lost. http://www.kaiku.com/winterwar.html The most reliable current estimate puts the figure at 270,000. Finland's losses were limited to around 22,830 men.
In the Moscow Peace Treaty of 12 March 1940, Finland was forced to cede the Finnish part of Karelia. The land included the city of Viipuri (the country's second largest), much of Finland's industrialized territory, and significant parts still held by Finland's army: over 10% of pre-war Finland. Some 422,000 Karelians - 12% of Finland's population - lost their homes. Military troops and remaining civilians were hastily evacuated; only a few score civilians chose to remain under Soviet governance.
Finland also had to cede a part of the Salla area, the Kalastajansaarento peninsula in the Barents Sea and four islands in the Gulf of Finland. The Hanko Peninsula was also leased to the Soviet Union as a military base for 30 years. While the Soviet troops had captured Petsamo during the war, they returned it to Finland according to the treaty.
As a whole, the peace terms were harsh for Finland. Russia received the city of Viipuri, in addition to their pre-war demands. Sympathy from the League of Nations, Western Allies, and from the Swedes in particular, did not prove to be of much help.
Little more than one year later, hostilities resumed with the Continuation War and a new chapter in the history of Finland began.
In 1948, Stalin wrote in Falsifiers of History that "there could hardly be any doubt that the leading circles of Finland were in league with the Hitlerites, that they wanted to turn Finland into a springboard for Hitler Germany's attack on the U.S.S.R." Regarding the start of the war, Stalin also wrote, "In the war which the Finnish reactionaries started against the Soviet Union, Britain and France rendered the Finnish militarists every kind of assistance. The Anglo-French ruling circles kept inciting the Finnish Government to continue hostilities."
See main article: Karelian question in Finnish politics. After the war, Karelian local governments, parishes and provincial organizations established Karjalan Liitto in order to defend the rights and interests of Karelian evacuees and to find a solution for returning Karelia. During the Cold War, President Urho Kekkonen tried several times to get the territories back by negotiating with the Soviet leadership, but did not succeed. No one openly demanded return. After the breakup of the Soviet Union, disputes were revived. Some minor groups in Finland have been actively demanding the peaceful return to Finland of the ceded territories. The most active group in this field is ProKarelia. In the latest polls, these demands have met with 26 - 38% support in Finland. Although the peaceful return of Karelia has always been on its agenda, Karjalan Liitto has, for the most part, stayed away from these demands.
The 1940 play There Shall Be No Night by American playwright Robert E. Sherwood was inspired by a moving Christmas 1939 broadcast to America by war correspondent Bill White of CBS. The play was produced on Broadway in 1940, and won the 1941 Pulitzer prize for Drama.
The 1940 story Biggles Sees It Through by W.E. Johns is set during the final stages of the war.
In 1989, the Finnish movie Talvisota was released. This film tells the story of a Finnish platoon of reservists from Kauhava. The platoon belongs to the 23rd Infantry Regiment, which consists almost solely of men from Southern Ostrobothnia.
The 2006 documentary shows how the Winter War influenced World War II and how Finland mobilized against the world’s largest military power.
In a 1992 column in Pelit, "Wexteen" (Jyrki J. J. Kasvi) lamented the difficulty of modelling the war in interactive entertainment. According to Wexteen, if the game mechanics are based on troop strengths, troops will march through Helsinki; if on historical events, through Moscow. The Winter War was featured in a scenario of the grand strategy game Hearts of Iron 2 and received dedicated games in the |wargame and the educational real-time strategy game .