# Winter War (1939)

URL: https://history-russia.com/timeline/1939-winter-war
Categories: battle

The Soviet Union attacked Finland on 30 November 1939. Finnish forces inflicted heavy losses, but the Moscow Peace Treaty of March 1940 forced Finland to cede Karelia. The USSR was expelled from the League of Nations. The war exposed the weakness of the purged Red Army. It convinced Hitler that the USSR could be defeated quickly.

## Why it matters
It convinced Hitler that the USSR could be defeated quickly.

Ruler at the time: [Joseph Stalin](https://history-russia.com/rulers/joseph-stalin)

## Sources
- [Wikipedia — Winter War](https://en.wikipedia.org/wiki/Winter_War)
- [Wikipedia — Stalinism](https://en.wikipedia.org/wiki/Stalinism)
- [Encyclopaedia Britannica topic lookup — Winter War](https://www.britannica.com/search?query=Winter+War)
- [Wikipedia — Timeline of Russian history](https://en.wikipedia.org/wiki/Timeline_of_Russian_history)