of the Salyes, Gnaeus Domitius Ahenobarbus,
the successor of Calvinus, penetrated into their own territory (632).
Up to this period the leading Celtic tribe had been spectators of the
encroachments of their Italian neighbours; the Arvernian king Betuitus,
son of the Luerius already mentioned, seemed not much inclined to enter
on a dangerous war for the sake of the loose relation of clientship
in which the eastern cantons might stand to him. But when the Romans
showed signs of attacking the Allobroges in their own territory,
he offered his mediation, the rejection of which was followed by
his taking the field with all his forces to help the Allobroges;
whereas the Haedui embraced the side of the Romans. On receiving
accounts of the rising of the Arverni, the Romans sent the consul
of 633, Quintus Fabius Maximus, to meet in concert with Ahenobarbus
the impending attack. On the southern border of the canton of the
Allobroges at the confluence of the Isere with the Rhone, on the
8th of August 633, the battle was fought which decided the mastery
of southern Gaul. King Betuitus, when he saw the innumerable
hosts of the dependent clans marching over to him on the bridge
of boats thrown across the Rhone and the Romans who had not a
third of their numbers forming in array against them, is said to have
exclaimed that there were not enough of the latter to satisfy the dogs
of the Celtic army. Nevertheless Maximus, a grandson of the victor
of Pydna, achieved a decisive victory, which, as the bridge of boats
broke down under the mass of the fugitives, ended in the destruction
of the greater part of the Arvernian army. The Allobroges, to whom
the king of the Arverni declared himself unable to render further
assistance, and whom he advised to make their peace with Maximus,
submitted to the consul; whereupon the latter, thenceforth called
Allobrogicus, returned to Italy and left to Ahenobarbus the no longer
distant termination of the Arvernian war. Ahenobarbus, personally
exasperated at king Betuitus because he had induced the Allobroges
to surrender to Maximus and not to him, possessed himself
treacherously of the person of the king and sent him to Rome, where
the senate, although disapproving the breach of fidelity, not only kept
the men betrayed, but gave orders that his son, Congonnetiacus, should
likewise be sent to Rome. This seems to have been the reason why
the Arvernian war, already almost at an end, once more broke ou