The Nervii or Nervians were one of the most powerful tribes of the Belgae in northern Gaul at the time of its conquest by Rome. Their core of their territory corresponded to the medieval County of Hainaut and contained a significant part of modern central Belgium, including Brussels and Mons, as well as stretching southwards to Cambrai in what is now France. During his first century BC Roman military campaign, Julius Caesar's contacts among the Remi reported that the Nervii were the most warlike of the Belgae, trekking long distances to take part in battles. Like the other tribes of northern Gaul, including the Menapii to the west, and the Eburones to the east, the Nervii were considered by Caesar to be relatively uncorrupted by civilization.