Finnish defenders sometimes, though very rarely, took fallen frozen Russian soldiers and posed them upright as psychological warfare. Although rare, a few cases have been documented. Common Russian soldiers and Finnish troops had a great deal of respect for the dead and would allow both parties to retrieve and bury their dead in peace and would make impromptu ceasefires for such occasions. Each party also buried the dead of the opposing side, left a stick on the ground marking the burial site and all the tags intact that would identify the dead.
The Soviet Union demanded that the Finns move the border between USSR and Finland back 25 kilometers from Leningrad and grant them a 30-year lease on the Hanko Peninsula for the construction of a naval base. The ultimate goal was to create a buffer zone around Leningrad. The Finnish refused and thus the Winter War started.
The Soviets began massing approximately one million men along the Finnish border. At the time, the entire population of Finland numbered around three million, while the Soviet Union was nearer to 171 million. The Finns knew they were out-manned at about one hundred to one, and therefore opted for a defensive, guerrilla-style strategy.
The weather during the War was the coldest Finnish winter ever registered. The cold caused considerable losses. The number of Red Army troops who froze to death is unknown. In one case during preparations for battle, the number of soldiers evacuated due to frostbite injuries was close to 10,000.
The Finns did also suffer a high number of frostbite cases. The most common reason for frostbite, on the Finnish side, was footwear. They were either poor civilian boots or, most often, military boots that were too small. The situation improved as proper boots were sent from the Home Front and the troops started to use captured Russian felt boots.
While the cold affected both sides, the Finns did have a significant edge, namely prewar training. While the Red Army was more trained to operate in the steppes of Russia, the Finnish Army had trained to fight in Finnish terrain and the Finnish weather, winter included. The skill of skiing was virtually universal among the Finns, while it was a rather rare skill on the Soviet side.
The Finnish military equipment was generally good for winter conditions, e.g. the infantry tent with the stove and the Finnish uniform tunic with the greatcoat. The Red Army did also have good winter equipment, in fact, some items valued even higher than their Finnish counterparts, namely the greatcoat and especially the felt boots.
Unfortunately, some Red Army units arrived at the Finnish front either without or with too few of them. Also, skis were surprisingly rare among the Red Army units.
As the temperatures dropped below -30 Celsius, some lubricants (as in artillery pieces or vehicles) started to freeze, as did the fluid in the recoil system in some artillery pieces. In some artillery weapons, the carriage failed in the cold, as the structure couldn’t withstand the extreme cold and the stress of firing. Both sides also had problems with artillery shells, as the fuses became unreliable.
The units of the Finnish Army were better suited for winter warfare than the Soviet units. The heavy equipment (lots of trucks, artillery, tanks) of the Soviet divisions kept them road-bound, while the lighter Finnish units were more maneuverable. The Finns relied mostly on horses. Horses consumed a lot of hay and had a rather poor cargo capacity, but the horses could move in the snow where a truck got stuck.