Accordingly, before the winter was ended, he marched with four legions unexpectedly into the territories of the Nervii, captured many men and much cattle, wasted their lands, and forced them to surrender and give hostages. He followed up his success by worsting the Senones, Carnutes, and Menapii, while Labienus defeated the Treviri. Gaul being tranquil, Cæsar, as he had determined, set out for Italy to hold the provincial assizes. There he was informed of the decree of the senate that all the youth of Italy should take the military oath, and he determined to hold a levy throughout the entire province. The Gauls, animated by the opportunity afforded through his absence, and indignant that they were reduced beneath the dominion of Rome, began to organise their plans for war openly. Many of the nations confederated and selected as their commander Vercingetorix, a young Avernian. On hearing what had happened, Cæsar set out from Italy for Transalpine Gaul, and began the campaign by marching into the country of the Helvii, although it was the severest time of the year, and the country was covered with deep snow. The armies met, and Vercingetorix sustained a series of losses at Vellaunodunum, Genabum, and Noviodunum. The Gauls then threw a strong garrison into Avaricum, which Cæsar besieged, and at length Cæsar's soldiers took it by storm. All the Gauls, with few exceptions, joined in the revolt; and the united forces, under Vercingetorix, attacked the Roman army while it was marching into the country of the Sequani, but they suffered complete defeat. After struggling vainly to continue the war, Vercingetorix surrendered, and the Gallic chieftains laid down their arms. Cæsar demanded a great number of hostages, sent his lieutenants with various legions to different stations in Gaul, and determined himself to winter at Bibracte. A supplication of twenty days was decreed at Rome by the senate on hearing of these successes. * * * * * TACITUS Annals