In 1939, the Soviet Union launched a war of aggression against Finland. The Soviet Union, believing that Leningrad was too close to the border, decided to force Finland to cede territory by force and annex Finland if necessary to restore the situation in Russian Finland during the Russian era. Finland, which had few soldiers, thought it was a limited border war, but did not expect to fight for more than three months, and although the Soviet Union reached a strategic intention, it also paid an extremely heavy price.
Finland is the coldest country in the world, with 1/4 of its territory in the Arctic Circle, and when it comes to the Winter War, the Finns are better than the Soviets. The Soviet-Finnish War coincided with the longest and coldest night of the year, and heavy snow and polar night severely limited the use of Soviet aviation and armored troops, but provided excellent opportunities for the Finnish army, which was good at skiing. The Finns made a living from fishing and hunting, and there were many hunters in the army who were active in the snow and ice all year round, and they formed ski teams in groups of three or five, which caused great damage to the Soviet army.
After 500,000 Soviet troops entered Finland, they were immediately under a total siege. The Soviet-Finnish border is densely forested and crisscrossed by water networks, but Finland has well-connected transportation that makes it easy to get strategic supplies to the front, while the Soviets have only one railway. After the war began, the Soviet heavy artillery was blocked in front of the Mannerheim Line, the logistics supply line was frequently harassed by the Finnish ski team, and the front-line troops were in a crisis of food and fire, and were killed in the snow by Finnish snipers one by one.
In the first phase of the war, the Soviet army dispatched 7 infantry divisions, 1 tank army and 2 tank brigades to carry out the attack, and the Finnish army relied on fortifications during the day to defend, and at night sent ski teams to harass the Soviet rear, specifically shooting the Soviet troops roasting in the snow. The Soviets attacked for more than a month without success, but were instead divided and surrounded by Finnish troops and forced to retreat. During the retreat, 2 infantry divisions were bitten by the Finnish army, and the rear road was cut off by the ski team, and they were immediately caught in a massacre.
The large Finnish forces then caught up and concentrated the strength of one army to besiege the two remnants of the Soviet army. After five days of fighting, about 20,000 Soviet troops were killed and frozen to death, most of the remaining were captured, only a few followed the division commander to break through, and the snow was full of ice sculptures and weapons left by the Soviet army. The offensive operation was unfavorable, and the Soviet high command was furious, venting their anger on the commander of the division that broke through, and was shot on the spot. However, the defeat of the Soviet army was due to insufficient preparation and poor command, and the division commander was only a scapegoat.