German armies took Allied forces by surprise in the Ardennes, marking the beginning of the Battle of the Bulge.
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Estonian tribes defeated Sweden in the Battle of Lihula.
The Ottoman Empire signed the Treaty of Adrianople with Russia, which ended the Russo-Turkish War.
Stephen III of Moldavia defeated the Ottoman Empire at the Battle of Vaslui.
The Battle of Bouvines began.
Adolf Hitler's German military attacked Moscow.
