Clermont is identified with the ancient Augustonemetum, the chief town of the Arverni, and it still preserves some remains of the Roman period.
In the time of Caesar the Arverni were a powerful confederation, the Arvernian Vercingetorix being the most famous of the Gallic chieftains who fought against the Romans.
Prominent among them, and dwelling in the division occupied by the Celts, were the Helvetii, the Sequani and the Aedui, in the basins of the Rhodanus and its tributary the Arar (Saone), who, he says, were reckoned the three most powerful nations in all Gaul; the Arverni in the mountains of Cebenna; the Senones and Carnutes in the basin of the Liger; the Veneti and other Armorican tribes between the mouths of the Liger and Sequana.
Early in 52 B.C. some Roman traders were massacred at Cenabum (Orleans), and, on hearing the news, the Arverni revolted under Vercingetorix and were quickly joined by other tribes, especially the Bituriges, whose capital was Avaricum (Bourges).
Caesar first besieged and took Avaricum, whose occupants were massacred, and then invested Gergovia (near the Puy-de-Dome), the capital of the Arverni, but suffered a severe repulse and was forced to raise the siege.