He soon had, amongst the Germans on the two banks of the Rhine and amongst the Gauls themselves, secret or declared allies.

He was joined by a young Gaul from the district of Langres, Julius Sabinus, who boasted that, during the great war with the Gauls, his great-grandmother had taken the fancy of Julius Caesar, and that he owed his name to him.

News had just reached Gaul of the burning down, for the second time, of the Capitol during the disturbances at Rome on the death of Nero.

The Druids came forth from the retreats where they had hidden since Claudius' proscription, and reappeared in the towns and country-places, proclaiming that "the Roman empire was at an end, that the Gallic empire was beginning, and that the day had come when the possession of all the world should pass into the hands of the Transalpine nations." The insurgents rose in the name of the Gallic empire, and Julius Sabinus assumed the title of Caesar.

War commenced.