The Gauls Wars (or Gallics) is called Julius Caesar s series of campaigns that began in April 58 BC and ended in September and October 52 BC, when, after a two-month siege, Caesar seized upon Alesia and imprisoned Vercingetorix, leader of the Gauls. The Gallic Strategy was to unite all the independent tribes of Gaul and expel the Roman invaders. To continue to meet this objective in the Operational Strategy, prior to the battle of Alesia, there was a transition - initially involuntary - from an indirect guerrilla offensive to a direct expectation defense. In the course of the battle, according to Vercingetorix s intention, the force in the oppidum should hold onto the Romans while an outside force would attack concentrically.