Moscow, Union of Soviet Socialist Republics March 13, 1940 (Finnish Time)

On this date in 1940, in the Soviet capital of Moscow, Finnish and Soviet dele­gates ini­tialed the Treaty (or Peace) of Moscow. The terms of the agree­ment, dated March 12 (Moscow time), ended the so-called Winter War the Soviets had unleashed a little over three months before when half a million Red Army troops stormed into the Kare­lian Isthmus. Home to Fin­land’s fourth largest city, Viipuri (now the Russian city of Vyborg), the isthmus was the eastern-most part of Fin­land and practically bordered on Lenin­grad (today’s St. Peters­burg), the Soviet Union’s second largest city and huge naval port with access to the Baltic Sea. The treaty ceded the 6,000‑sq‑mile/­15,500‑sq‑km isthmus to the Soviet Union, and the entire Karelian pop­u­la­tion—about 422,000 people—was evacuated to other parts of Finland.

The surprise Soviet thrust into the Karelian Isthmus on Novem­ber 30, 1939, was prompted by fears that Nazi Germany could possi­bly stage an attack on the Soviet Union through Finland. Normally such para­noia should have dissi­pated several months earlier in the wake of the long-antag­o­nistic nations having con­cluded a 10‑year bilat­eral non­aggres­sion pact, the Molotov-Ribben­trop Pact with its secret proto­cols for divvying Finland, the Baltic States, and Poland into twin spheres of influ­ence. Never­the­less, Soviet repre­sen­ta­tives continued to badger their Finnish neighbors into swapping, ceding, or leasing land that would have pushed the Finnish Karelia border away from Lenin­grad and its approaches, but the Helsinki govern­ment either kept demur­ring or did diplo­ma­tic do-si-dos right up through Novem­ber. When Soviet warriors did strike their neighbor of 3.7 mil­lion people, one day after severing diplo­matic rela­tions with Finland, they ex­pected an easy victory because strength in man­power, armor, and air­craft was all on their side. Certainly, they thought, by next month’s end, when Soviet dictator Joseph Stalin’s 60th birthday rolled around on December 21, 1939, victory would be theirs.

Alas for Soviet war planners things began falling apart almost immedi­ately. The League of Nations deemed the Soviet attack illegal, expelled the Soviet Union from its organi­za­tion, and urged other nations—among them Great Britain, France, Italy, Sweden, and the U.S.—to aid Finland. Worse, Red Army khaki uni­forms allowed Finnish sharp­shooters to kill or wound tens if not hun­dreds of thou­sands of enemy sol­diers against snow-white back­grounds. Soviet casual­ties—many attri­buted to frost­bite and star­va­tion—even­tu­ally numbered between 321,000 and 381,000, with some 5,500 taken pri­soner. Noisy Soviet armor and long columns of men and artil­lery traveling over the area’s few roads in dense forests and swamps also made inviting targets to ambush and destroy. The Soviets lost between 1,200 and 3,500-plus tanks and maybe 1,000 air­craft during the course of the war. After two months of debili­tating losses the Soviet mili­tary reor­ga­nized, flooded the theater with new tanks, artil­lery pieces, air­craft and men, and adopted more effective tactics that wore down the Finns.

Russo-Finnish hostilities ceased in March 1940 with the signing of the Moscow Peace Treaty. Finland ceded 11 per­cent of its terri­tory, repre­senting 30 pe­rcent of its eco­nomic assets, to the Soviet victors. Finland retained its sover­eignty. Fifteen months later, in June 1941, Finland joined Nazi Germany in declaring war against the Soviet Union. The Winter War of 1939–1940 was thus followed by the Contin­u­a­tion War (June 25, 1941, to Septem­ber 19, 1944) between the former co-bel­lig­er­ents. The second war trans­lated into another Soviet tacti­cal victory, this time accom­panied by Finland paying $300 mil­lion in war repa­ra­tions to the USSR. Because of Nazi Ger­many’s partic­i­pa­tion in the 1941–1944 period, a lack of con­sen­sus exists regarding the human and material losses in the Continuation War.

Finland’s Winter War, Late November 1939 to Mid-March 1940

Finland’s Winter War: Soviet tankFinland’s Winter War: Downed Soviet plane

Left: A solitary Soviet T-26 Model 1937 tank rolls through a wintery Finnish forest. The under­equipped Finns ini­tially struggled to counter the Soviets’ armored columns. A cheap weapon Finns used against armored vehicles was Molotov cock­tails, glass bottles filled with gaso­line and tar that could be thrown at enemy targets. The Finns esti­mate that the num­ber of lost Soviet tanks was 1,000–1,200 while their tank losses were 20–30.

Right: A Finnish patrol is seen here picking apart a downed Soviet air­plane, perhaps after a Soviet sortie had gone bad. Much of the wea­ponry used by Finns during the Winter War was captured from the enemy. The Soviet Air Force lost around 1,000 air­craft. Just over half of the Soviet losses were combat casualties. Finns lost 62 aircraft.

Finland’s Winter War: Finnish riflemenFinland’s Winter War: hidden Finnish riflemen

Left: Blending in with their surroundings these Finnish rifle­men, out­gunned and out­numbered by the enemy, used the advan­tages a Nordic winter pro­vided with remark­able effect. Invading Red Army troops ini­tially wore dark or khaki-colored uni­forms, making them easy targets for sharp­shooters. One Finnish sharp­shooter, Simo Häyhä, had 542 con­firmed Soviet kills during the Winter War before he was seriously wounded by a Soviet marksman. His remark­able story is told in The White Sniper.

Right: Dressed in white camou­flage, these Finnish defenders were almost impos­sible for the enemy to see in the snow-dusted forests through which they moved.

Finland’s Winter War: Dead Soviet soldiersFinland’s Winter War: Wounded Soviet soldiers

Left: As Soviet troops and vehicles filed along forest roads, Finnish ski troops were able to steal­thily move into posi­tion and destroy vehi­cles at the front and rear of the column. With the road blocked, Finnish defenders could then encircle and destroy the trapped Red Army. In this photo dead Soviet soldiers lie in the after­math of a deva­stating attack on their column during the Battle of Raate Road, which took place during the first week of Janu­ary 1940. Soviets losses were put at between 7,000 and 9,000 men. The Russian State Mili­tary Archive con­firms that 167,976 Soviet sol­diers were killed or went missing during the 105-day Winter War. For their part, Finnish his­to­rians esti­mate 25,904 of their country­men died or went missing and 43,557 were wounded in the Winter War.

Right: Wounded and freezing Red Army soldiers after their capture in February 1940. The Finns held some 5,572 Soviet POWs at the con­clu­sion of the war, while the Soviets held 800–1,000 Finns. It is believed most of the Soviets who were repa­tri­ated to their home­land were killed in camps run by the Soviet secret service, the NKVD.

The Winter War Between the Soviet Union and Finland, 1939–1940