Battle of Alesia

The Battle of Alesia (52 BC) was the decisive engagement of the Gallic Wars, fought around the hilltop oppidum of Alesia, a stronghold of the Mandubii in central Gaul. After a pan-Gallic revolt led by Vercingetorix of the Arverni had overrun Roman territory and cost Caesar a defeat at Gergovia, the Gallic leader withdrew into Alesia with his army. Caesar besieged the town with roughly ten legions, ringed the plateau with a fortified line of circumvallation, and — when a vast Gallic relief army arrived — added a second line facing outward. Ancient sources put the relief force at a quarter of a million men or more; modern estimates are far lower, but it still outnumbered the Romans. Coordinated Gallic attacks from inside and outside came close to breaking the ring, especially at the weak northern camps, where Caesar himself led the counter-attack in person. The relief army disintegrated after its final assault failed, and the starving town surrendered. Vercingetorix laid down his arms to save his followers and was held for six years before being paraded in Caesar's triumph and executed. Alesia ended organised Gallic resistance and turned Gaul toward Romanisation, while giving Caesar the wealth, veterans, and fame that made his later march on Rome possible.