The Battle of Bibracte was fought between the Helvetii and six Roman legions, under the command of Gaius Julius Caesar. It was the second major battle of the Gallic Wars.

After following the migration of the Helvetii and defeating them, Caesar, around 20 June, moved towards Bibracte (approximately 18 miles away from their camp) to obtain the supplies promised by his allies, the Aedui. Informed by deserters of Lucius Æmilius, commander of the cavalry, the Helvetii took this occasion to turn and harass Caesar's rear guard. When Caesar observed this, he sent his cavalry to delay the attack. He placed the Seventh (Legio VII Claudia), Eighth (Legio VIII Augusta), Ninth (Legio IX Hispana), and Tenth legions (Legio X Equestris), organized in Roman fashion (triplex acies), at the foot of a nearby hill, the top of which he occupied himself, along with the Eleventh (Legio XI Claudia) and Twelfth (Legio XII Fulminata) Legions and all his auxiliaries. The baggage train was also assembled near the summit, where it could be guarded by the forces present there.

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