The Bellovaci were among the most powerful and numerous of the Belgian tribes of north-eastern Gaul conquered by Julius Caesar in 57 BC. The name survives today in the French city of Beauvais, called by the Romans Caesaromagus.
The territory of the Bellovaci extended from modern Beauvais to the Oise River, along the coast. Beauvais is a French city approximately 77.6 kilometers north of Paris. The Bellovaci neighboured six tribes, the Ambiani, Viromandui, Suessiones, Veliocasses, Caleti and Parisii.
The Bellovaci meant, possibly, the "shouters", the root word bel- is found in the Irish word beal, which means mouth and also Bel Bial means WHITE in other Indo-European languages. The Latin word bellum means war, and the root vac- means empty. However, there is no known record of a naming of the Bellovaci. The bell- root is also present in the name of Bellona, an Ancient Roman goddess of war.
This campaign occurred in the Compiègne Forest, in an area that had been occupied by the Suessiones. The Bellovaci intended to conquer this territory, a situation that Julius Caesar feared would expand into a greater threat and he decided it would be useful to correct the conflict to prove Roman superiority.
Bellovaci employed guerrilla warfare, in particular targeting Roman foragers. Meanwhile, Caesar's strategic plan was to draw the Bellovaci forces out into open ground.
Caesar ordered troops into the territory of the Suessiones, but chose to confront the Bellovaci himself. The Bellovaci, led by Correus, camped at Mount St. Marc, intending to attack head on if Caesar brought three legions, and to use guerrilla tactics if he brought more. The Roman camp was located at Mount St. Pierre, and heavily fortified with two ditches and two lines of defendants. The events of this campaign were recorded by Aulus Hirtius, though his findings do not entirely correspond with the geography of the region – he provided only that the Bellovaci camped at a “high wooded place surrounded by marsh”.