Swedish intervention in the Winter War

See also: Swedish Volunteer Corps

The Winter War began on 30 November 1939 with a Soviet invasion of Finland, which resulted in initial failure because of the motivation and tactics used by the Finns. However, the Soviets soon pushed an enormous force into Finland and without help from the Allies nor Axis, Finland could only rely on Sweden for military assistance, which proved to be crucial for Finland's survival as a nation. The Swedish government officially called the intervention an action of volunteers, while it in fact was a complete military intervention. The exact date when the operation began is unknown even today, but the first Swedes officially fighting in the Winter War fought in February, 1940.

Background to the Swedish intervention
On 19 February 1940, the King of Sweden Gustav V publicly rejected pleas from Finland's government for military intervention in the Winter War to help defend Finland against the Soviet invasion. This statement from the king was aimed at maintaining Swedish neutrality and to quiet a strong Swedish public opinion advocating participation in the war. The statement had this effect, but also produced substantial bitterness in Finland. However, the king was not the head of government and could not control Swedish foreign politics. The Swedish government under Per Albin Hansson immediately begun making plans for military deployment along Finland's border in response to the Finnish pleas for help. And although no formal alliance had been concluded, Swedish and Finnish intelligence agencies cooperated in secret to such an extent that they exchanged all available information obtained by espionage, not only against the Soviet Union but also the Western Allies, who had threatened Sweden on multiple occasions. Because of the Swedish neutrality policy, however, no formal intervention could be commited - only a secret military aid program under the title "volunteers". Sweden was in fact during this time at war with the Soviet Union, although no formal declaration of war had been made. Sweden also withdrew their forces from Finland after the surrender of the Finnish government in March 1940.

Swedish-Soviet clashes
The Soviet Union and Sweden had many disagreements to begin with, including:
 * Previous grievances (Sweden and Russia had fought many times, and it was Russia who had "stolen Sweden's rightful place as a world-dominating great power".
 * Soviet submarine incidents (on multiple occasions before, during and after the war, Soviet submarines had entered Swedish waters for the purpose of espionage, staining diplomatic relations)
 * Swedish support for Germany (the Swedish government had spoken in support for Germany on multiple occasions)

The first clash between Swedish and Soviet forces occured in the Battle of Salla, where 9,400 Scandinavian (mainly Swedish) soldiers attacked and reclaimed a number of forts that had been conquered from Finland by the Soviet Army. The volunteers lost 23 men to enemy bullets, and another 7 were captured. Soviet casualties rose well above 300 according to Finnish sources (Swedish sources claim 5,000 killed and 8,000 wounded along with 180 prisoners of war).

Sweden
The Swedish Volunteer Corps consisted of a total of 9,640 men, although only 8,402 fought in the frontlines. The rest were engineers, medics, spies, saboteurs or military-related labour forces. The Swedish Volunteer Air Force had 25 aircraft, models 1920-1935, giving a very limited ability for accurate bombing runs. The Swedes also commanded 1,010 Danes and 895 Norwegians, giving a total of 11,545 troops. No tanks or armoured vehicles were used by the Swedish forces during the intervention, as they relied on mobility. However, almost a hundred howitzers and anti-tank guns of Swedish design was deployed throughout Finland during the war. The Swedish Volunteer Corps casualties included:

28 dead

50 wounded

140 disabled by frostbite

2 anti-tank guns destroyed

1 aircraft heavily damaged

Finland
Between 337,000 and 346,500 Finns fought in the Winter War as a whole. However, it is not known how many of these fought alongside the Swedes. Finland also deployed 32 tanks and 114 aircraft, few of these actually being able to fight alongside the Swedish intervention force. Throughout the Winter War, Finnish casualties included:

25,904 dead or missing

43,557 wounded

1,000 captured

957 civilians killed in air raids

20-30 tanks

62 aircraft

Soviet Union and FDR
The Soviet Union and the Finnish Democratic Republic had fielded an army of 760,578 men (some sources state 998,100 men, or as many as a million if including non-fighting auxiliaries), supported by 6,541 tanks, 3,880 aircraft and thousands of artillery pieces. Soviet casualties throughout the war were enormous and much more devastating than the enemy losses, and many Soviet soldiers have supposedly died only because of the Swedish intervention. In total, the Soviet union lost:

126,875 dead or missing

188,671 wounded, injured, burned or disabled by frostbite

5,572 men captured

3,543 tanks destroyed, disabled or captured

515 aircraft shot down