In the years 58-51 BC, Gaul was conquered and added to the Roman Empire through the military campaigns of Julius Caesar and his legions. For the first time in history, tribal groups in north-western Europe were confronted with the violent expansionism of an imperial system.
Although Caesar’s war narrative is coloured by personal propaganda and imperial ideology, there is no doubt that the conquest had dramatic consequences for Gallic societies. The Roman writer Appian claimed that Caesar killed one million Gauls and enslaved another million out of a total population of four million.
Until recently, Caesar’s conquests in the northern periphery of Gaul were known only from his historical account. In the Netherlands, Belgium, and the German Lower Rhine area, the Caesarian conquest was almost totally invisible archaeologically. Direct evidence in the form of Roman army camps or battlefield locations was absent.
One of the most spectacular discoveries of Roman provincial archaeology of the past few years is the identification of a Late Iron Age fortification at Thuin as the oppidum of the Aduatuci. For the first time in northern Gaul, archaeology can identify one of the major ‘crime scenes’ described by the Roman proconsul. This site was conquered by Caesar in 57 BC as part of his campaigns against the tribes of the Nervii and the Aduatuci. The fortification of Thuin (Belgium) occupies a plateau of more than 13ha and can be reached on the eastern side via a narrow, 60m-wide finger of land. Several arguments indicate this to have been the oppidum of the Aduatuci. The historical account has it that, after the site’s capture, the entire population of 53,000 individuals were sold as slaves and deported to Italy:
“On the morrow the gates [of the oppidum] were broken open, for there was no more defence, and our troops were sent in. Then Caesar sold as one lot the booty of the oppidum. The purchasers furnished a return to him of 53,000 persons.”
The main arguments for the identification of Thuin are as follows: it was an important Late Iron Age fortification situated in the territory of the Aduatuci that did not survive into the Roman period; there is a close match with the topography described by Caesar; several gold hoards of the early 50s BC have been found and these seem to reflect a single event; finally, and most importantly, concentrations of Roman lead sling-bullets imply a Roman siege of the site.
The sling-bullets appeared in two separate concentrations: on the wall near the main entrance of the fortification, and on the far side of the Biesmelle River. Their concentration at the main rampart strongly suggests that they were used by the attackers.
These maps and extract of text appeared within the feature on Caesar’s Gallic War in issue 56 of Military History Monthly.