German armies took Allied forces by surprise in the Ardennes, marking the beginning of the Battle of the Bulge.
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The Battle of Bouvines began.
The Battle of Stamford Bridge occurred between the English army and a Norwegian force.
The Potsdam Conference began between the Soviet Union, UK & US.
The English were defeated at the Battle of Stirling Bridge.
The Treaty of Granada was signed, marking the end of the Grenada War, which started in 1482.