Brennus is the name of two Celtic chieftains famous in ancient history:
2. In 279 BC, another army of Celts led by one Brennus invaded Macedonia and northern Greece. The following year they crossed the Bosporus and settled in a part of Asia Minor that came to be called Galatia.
Geoffrey of Monmouth also writes in his Historia Regum Britanniae about a personage named Brennius who conquers Rome. He probably created this character from the two Brenni of history.
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