Marcus Junius Brutus (85 - 42 BC) was a historical figure. He was a nephew of Cato the Younger, son of Servilia Caepionis and suspected biological son of her lover Julius Caesar. He is best known for assassinating Caesar in 44 BC. He then fought an extended civil war against Caesar's political heirs Mark Anthony and Octavian. He commited suicide after loosing said war.
In the Asterix comics, Brutus is an adoptive son to Caesar and wants to succeed him by any means possible. He sought to assassinate his adoptive brother Caesarion, leading to Cleopatra entrusting her son to Asterix. Relentless, Brutus managed to burn Asterix's village to the ground and was only stopped by Caesar himself. So far Brutus has been the most effective enemy of the villagers.