This timeline's point of divergence is in the first millennium A.D., where Celtic Tribes refuse to accept the rule of the Roman Empire and unite against the Romans to establish a dominant power in Europe.
First Millennium A.D.
As the Roman Empire grows in both population and territorial expansion, people begin to either accept Roman rule or get conquered by Rome's superior military. Meanwhile, the advanced Celtic Civilisation was being conquered by the Germans to the north, the Slavs to the east and the Romans to the south.
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