Please note that Mommsen uses the AUC chronology (Ab Urbe Condita), i.e. from the founding of the City of Rome. You can use this reference table to have the B.C. dates
From: The History of Rome, by Theodor Mommsen
Translated with the sanction of the author by William Purdie Dickson
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 out, and a second appeal to arms took place at Vindalium (above Avignon) at the confluence of the Sorgue with the Rhone. The result was not different from that of the first: on this occasion it was chiefly the African elephants that scattered the Celtic army. Thereupon the Arverni submitted to peace, and tranquillity was re-established in the land of the Celts.(3)
3. The battle at Vindalium is placed by the epitomator of Livy and by Orosius before that on the Isara; but the reverse order is supported by Floras and Strabo (iv. 191), and is confirmed partly by the circumstance that Maximus, according to the epitome of Livy and Pliny, H. N. vii. 50, conquered the Gauls when consul, partly and especially by the Capitoline Fasti, according to which Maximus not only triumphed before Ahenobarbus, but the former triumphed over the Allobroges and the king of the Arverni, the latter only over the Arverni. It is clear that the battle with the Allobroges and Arverni must have taken place earlier than that with the Arverni alone.
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