1939 – 1940
The Soviet Union invaded Finland on November 30, 1939 after failed territorial negotiations and the disputed Mainila shelling used as a pretext. Finnish forces exploited terrain, mobility, local initiative, and Soviet operational failures to win striking defensive victories, but the Red Army adapted, broke the Mannerheim Line, and compelled the March 1940 Moscow Peace Treaty. Finland preserved independence but ceded more territory than Moscow had originally demanded and evacuated hundreds of thousands of residents. Soviet losses were much higher, though ratios and exact figures remain disputed. The war influenced later strategic perceptions, but it did not by itself convince Hitler to invade the Soviet Union; Finland later fought as Germany’s co-belligerent in the Continuation War.
Chapter-by-chapter narrative with maps, primary sources, and key events.
Explore battles on a live map with a timeline slider and territory overlays.
Deep-dive into every major engagement — commanders, casualties, significance.
Biographical flip cards with real portraits, facts, and full biography pages.
Trace each figure's full life journey — birth, education, battles, and death — on a live map.
Scroll-driven visualization of casualties — each dot a thousand lives.
Weapons, war machines, and the military innovations that defined how this conflict was fought.
Cause-and-effect chains tracing the war's long shadow on history.
War crimes, massacres, and the darkest chapters of this conflict — documented for history.
The Soviet Union invaded Finland on November 30, 1939 after failed territorial negotiations and the disputed Mainila shelling used as a pretext. Finnish forces exploited terrain, mobility, local initiative, and Soviet operational failures to win striking defensive victories, but the Red Army adapted, broke the Mannerheim Line, and compelled the March 1940 Moscow Peace Treaty. Finland preserved independence but ceded more territory than Moscow had originally demanded and evacuated hundreds of thousands of residents. Soviet losses were much higher, though ratios and exact figures remain disputed. The war influenced later strategic perceptions, but it did not by itself convince Hitler to invade the Soviet Union; Finland later fought as Germany’s co-belligerent in the Continuation War.
Finnish Winter War was fought from 1939 to 1940.
Finnish Winter War was fought between Finland and Soviet Union.
An estimated 151,957 people died in Finnish Winter War, including roughly 151,000 military and 957 civilian deaths. Figures are scholarly estimates and vary by source.
Major engagements included Battle of Taipale, Battle of Kollaa, Battle of Suomussalmi, and Soviet Breakthrough at Summa.