📅 On This Day in Military History
2 events across history
After a month-long reorganization under the newly appointed Marshal Semyon Timoshenko, the Soviet Northwestern Front launched a massive prepared assault against the Summa sector of the Mannerheim Line on February 11, 1940. Preceded by days of intense artillery bombardment involving over 3,000 guns — one of the most concentrated artillery barrages in history to that point — Soviet forces finally breached the Finnish defenses. Finnish troops, exhausted after 75 days of continuous combat and desperately short of ammunition and replacements, could not plug the gap. The Mannerheim Line had been broken.
The breakthrough at Summa ended the first phase of the Winter War and fundamentally altered its character. The Finns had held for 75 days against overwhelming odds but could not sustain resistance indefinitely without external support that never came.
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Roosevelt, Churchill, and Stalin concluded eight days of negotiations at the Crimean resort of Yalta, agreeing on the post-war division of Europe, Soviet entry into the Pacific War, and the founding of the United Nations.
Yalta's agreements shaped the Cold War world order for the next 45 years, with critics arguing Roosevelt conceded too much to Stalin over Eastern Europe.
Outcome
Post-war world order established; Cold War division begins