In the winter of 53 BC, after Caesar had crossed the Alps for Cisalpine Gaul, new discontent was brewing among the tribes of southern central Gaul. With the absence of legions in their territories, and certainly resisting the Roman yoke, the Carnutes rose up and wreaked havoc on a small Roman settlement called Cenabum, near modern Orleans. The small town of Roman traders was slaughtered by the Gauls, and word quickly spread throughout the region of the uprising.
Among those tribes who heard the word, and the call for solidarity against Rome, were the neighboring Arverni. Initially hesitant a young chieftan, Vercingetorix (or in Gallic possibly Fearcuincedorigh, Man who is chief of a hundred heads), came to forefront to rally the Gauls. He was the son of Celtillus, a former chieftan who was executed for attempting to unite the tribe under a single king. His son seemed to be following in the father's footsteps, but times were changing, and desperation was setting in. Vercingetorix was expelled from the capital of the Arverni by his own uncle, who protested against revolt, but the young man was resilient and recruited like minded tribesmen from the countryside. He was able to regain entry to the city, and with his small growing army in tow, was named chief of all the Arverni.
Other neighboring tribes soon joined the growing revolt, especially in the absence of the legions who occupied the northern and eastern portions of Gaul. According to Caesar, the Senones, Parisii, Pictones, Cadurci, Turones, Aulerci, Lemovice and the tribes of Aquitania all joined in the general revolt. The real danger came when this new coalition began making inroads into the Aedui, the most formidable and oldest of the Roman allied tribes. Caesar had to make haste from Cisalpine Gaul and back across the Alps to his army, but the mountains were still buried in snow from the winter. Caesar reports that his men dug 6 feet of snow from their path in order to make the crossing and he was able to do so at an alarming speed. Finally joining his army in the late winter early spring of 52 BC, Caesar had no choice but to consolidate his forces against the formidable revolt. The danger here was that it reduced garrisons, allowing other tribes to rise up, and the terrible situation with trying to feed such a large force. Vercingetorix wisely adopted a plan to slash and burn what food stores would be readily available to Caesar, and the tribes mostly complied. However, one town, Avaricum, with its great food stores, was spared as the owning tribe had already burned 20 of their own towns.
Caesar, joined by Germanic Ubii cavalry and a poorly fed army made haste for Avaricum and delaying tactics by the Gauls were mostly fended off by the Ubii. Caesar arrived at the fortified city in early spring and began displaying his tactical brilliance in siege warfare. Despite incessant rain, two wheeled towers, eighty feet high, with 330 foot ramps were constructed to penetrate the defenses. Despite desperate fighting to prevent the Romans from overtaking the walls, Caesar, after 27 days, entered the town. The population in its entirety was put to the sword. The Romans, frustrated and half-starved spared very few, and of 40,000 reported inhabitants, only 800 supposedly escaped to inform Vercingetorix. Well fed and encouraged by victory, Caesar could now plan on attacking the main body of his Gallic opponent directly. Vercingetorix won more support through the Roman victory, however. Seeing the wisdom of his plan to destroy the food supply more tribes united under the Arverni King. He was slowly becoming, if not a King, then at a minimum, the commander in chief of all the combined Gallic tribes.