Gaul thus came voluntarily, in the persons of her chiefs, to throw herself into the arms of Cæsar, take him for the arbiter of her destiny, and implore him to be her saviour. He spoke encouragingly, and promised them his support. Several considerations engaged him to act upon these complaints. He could not suffer the Ædui, allies of Rome, to be brought under subjection by the barbarians. He saw a substantial danger for the Republic in the numerous immigrations of fierce peoples who, once masters of Gaul, would not fail, in imitation of the Cimbri and Teutones, to invade the Roman province, and thence fall upon Italy. Resolved to prevent these dangers, he proposed an interview with Ariovistus, who was probably occupied, since the defeat of the Helvetii, in collecting an army among the Triboci (towards Strasburg),[205] as well to oppose the further designs of the Romans, as to defend the part of the country of the Sequani which he had seized. Ariovistus, it will be remembered, had been declared, under Cæsar's consulate, ally and friend of the Roman people; and this favour would encourage the expectation that the head of the Germans would be willing to treat; but he refused with disdain the proposed interview. Then Cæsar sent messengers to him to reproach him with his ingratitude. "If Ariovistus cares to preserve his friendship, let him make reparation for all the injury he has inflicted upon the allies of Rome, and let him bring no more barbarians across the Rhine; if, on the contrary, he rejects these conditions, so many acts of violence will be punished in virtue of the decree rendered by the Senate, under the consulate of M. Messala and M. Piso, which authorises the governor of Gaul to do that which he judges for the advantage of the Republic, and enjoins him to defend the Ædui and the other allies of the Roman people."
By this language, Cæsar wished to show that he did not violate the law, enacted a year before under his consulate, which forbade the governors to leave their provinces without an order of the Senate. He purposely appealed to an old decree, which gave unlimited powers to the governor of Gaul, a province the importance of which had always required exceptional laws.[206] The reply of Ariovistus was equally proud:--