After this great success, the barbarians, instead of pursuing their advantage, spread through the province and formed an alliance with the Volci Tectosages, who had their capital at Toulouse. Then they hurried towards Northern Gaul. The consul Cœpio was sent to chastise the Volci for their defection, and he took and pillaged Toulouse. The Cimbri and Teutons, on hearing of this, retraced their steps and confronted Cœpio. But a year was allowed to pass without any decisive action being fought.
In the meantime a fresh army had been raised in Rome, and despatched to the aid of Cœpio, under the command of Manlius. In a fit of jealousy Cœpio retired to the left bank, encamped apart, and refused to hold any communication with Manlius; and, that he might have an opportunity of finishing the war himself, he pitched his quarters between Manlius and the enemy. At this juncture, with such a formidable host threatening, the utmost prudence and unanimity were needed by the two commanders; this the soldiers perceived, and they compelled Cœpio, against his will, to unite his forces with those of Manlius. But this did not mend matters. They quarrelled again, and again separated. The barbarians, who were informed as to the condition of affairs, now fell on one army and then on the other, and utterly routed both. Eighty thousand Roman soldiers and forty thousand camp followers perished; only ten men are said to have escaped the slaughter. It was one of the most crushing defeats the Romans had ever sustained, and the day on which it happened, October 6th, became one of the black days in the Roman calendar.
This overwhelming victory opened to the barbarians the gates of Italy. It was, however, decided by them to ravage Spain before invading Italy. The whole course of proceedings on their part was marked by a series of fatal blunders. Accordingly they crossed the Pyrenees, but met with such stubborn resistance from the Iberians that they withdrew.
Meanwhile, Rome had recalled Marius from Africa, where he had triumphed over Jugurtha, King of Numidia, along with some of his victorious legions; and to him was entrusted the defence of Italy. He hastily raised a new army, hurried into the province, crossed the _crau_, and planted himself at the extreme western end of the chain of Les Alpines at Ernaginum, now S. Gabriel, whence he could watch the enemy; and whilst there he employed the soldiery in digging a canal from the sea to the Durance, by means of which his camp could be supplied from Marseilles with munitions of war and provisions.