Treaty of Moscow

Russo-Finnish history [1940]

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July 16, 2026

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The Treaty of Moscow, signed on March 12, 1940, concluded the Russo-Finnish War (also known as the Winter War). This conflict began when the Soviet Union attacked Finland on November 30, 1939, after Finland rejected Soviet demands for territory on the Karelian Isthmus, a naval base at Hanko, and islands in the Gulf of Finland. These demands were made to secure Leningrad. Despite strong Finnish resistance, the Soviet Union eventually breached the Mannerheim Line. The treaty forced Finland to cede a significant portion of southeastern Finland, including the city of Viipuri (Vyborg), and lease Hanko to the Soviet Union for 30 years. This treaty was later reaffirmed after the "War of Continuation".123

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Finland
The Winter War
By the Treaty of Moscow of March 12, 1940, Finland surrendered a large area of southeastern Finland, including the city of Viipuri (renamed Vyborg), and leased the peninsula of Hanko to the Soviet Union for 30 years.
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By the Treaty of Moscow of March 12, 1940, Finland surrendered a large area of southeastern Finland, including the city of Viipuri (renamed Vyborg), and leased the peninsula of Hanko to the Soviet Union for 30 years.
Read More