How old is English?
Most modern French websites continue to propagate the idea that most Belgians, and certainly the Nervians, were Gauls.
Belgium was at the time an association of tribes. The "bravest of all Gauls" were not the modern Belgians. It were the populations situated between the Somme river and the Seine river. They were within the ancient Belgian association and spoke in contrast to the northern Germanic speaking tribes, a Gaulish language. This region is today very much France.
Caesar wrote lies
He declared all land between the Pyrenees and the Rhine to be 'Gaul'. This territory simply corresponded with what he had conquered. Compare with the notion 'Arab country'. For many Americans this includes Iran, although Iran shares only its religion with the Arabs. Everything else is different, even more different then between modern Germans and Italians.
Old language border
A rather surprising conclusion for the modern Belgians is that there was a language border some 2000 years ago, but much more to the south. Most of the French départements "Nord" and "Pas de Calais" were Germanic speaking. This is in complete contrast to the French view which situates the border somewhere in southern Holland.
 Germany itself lay on the eastern side of the Rhine. Belgians refused to be called Germans.
 Trier, the civitas of the Treveri, today the people of Luxemburg, was also situated just outside the tribal territory.
At the time of Julius Caesar the entire territory of modern Belgium spoke a Germanic language which we can call proto-Flemish.
This is why:
"Treveri et Nervii circa adfectationem Germanicae originis ultro ambitiosi sunt, tamquam per hanc gloriam sanguinis a similitudine et inertia Gallorum separentur."
This sentence was written by the Roman historian and chronicler Tacitus in his book "Germania" (Latin: De Origine et situ Germanorum). It is widely accepted that Tacitus obtained most of his knowledge about German tribes from hearsay, as he never wandered far beyond the Rhine border into Germania. The sentence above however tells us something about Germans from within the Roman Empire. So he must have got this information first hand. The sentence can be translated literary as follows: "The Treverians and Nervians affectionate to the highest level their German origin, they say the nobility of this blood separates them from any comparison with [the Gauls] and from the laziness of the Gauls." In other words: both tribes didn't like to be confused with Gauls. They were of German origin (but they didn't like to be called Germans either - this is mentioned elsewhere). According to them, Gauls lacked a sense of honour (not noble or serious enough) and were lazy.
It is today still the opinion of many Flemish that the French are lazy.
"I O M COH I NERVANA GERMANORVM MIL EQ CVI PRAEEST Q IVS G F CLAVD ASINIANVS TRIBVNVS". An inscription recovered from an undated altar stone in the fort near Burgh-by-Sands (North England). "To Jupiter, Best and Greatest (a classic formula), Germanic Nervia's First Cohort, 1000 strong, parmounted (cavalry), under the command of tribune Quintus Claudius Asinianus, devoted son of Gaius". The mention 'Germanic Nervia' or 'Nervia of the Germans' can leave no doubts: the homeland of the Nervians was in the proto-Flemish part of Belgium.
Gaius Julius Caesar had reported in his book "De bello Gallico" that he almost had lost the battle of the Sabis river against the
Nervians. This fact and the fact that Caesar allegedly wrote that the "Belgians are the bravest of all Gauls" made the French
historians believe in the 19th century that the Nervians had to be Gauls.
Belgica or Belgium (both names were used by Caesar) was an association of northern Germanic (but not German  ) and southern Gaulish tribes. Amongst them, the Nervians were considered to be the most powerful. Caesar never said anything specific about their origin. This is probably no coincidence. Caesar had orders to pacify the Gauls, not the Belgians. By conquering Belgium he exceeded his territorial mandate (= 'Gaul itself' as he named the center of modern France), he had disobeyed explicit orders. By forgetting to mention the origin of the Nervians, or even by suggesting that they were Gauls, he avoided giving his enemies in Rome too clear an idea of what he really was doing.
For French historians Caesar's 'interpretation' was welcome: until 1850 the annexation of Belgium had been a fixed part of the French long-term political agenda. As Caesar had clearly mentioned that two northern Belgian tribes were of German origin, the Menapians and Eburones, these tribes were located by French historians as far north as possible upon the ancient Belgian maps, preferably half in (modern) Holland. By contrast, the (allegedly Gaulish) Nervian tribe was located as far south as possible, in the southern (French speaking) half of Belgium. Had Cambrai (a city in northern France) not been the capital of the Nervians? According to that 'information', French historians were convinced that the Nervian tribe had to be a Gallic tribe. This was clearly an unashamed distortion of history. That theory also provided the 'proof' that all of Belgium once was Gaul (read: French) and had to be re-integrated into France. It suited the French political needs of the 19th century. The Belgians had to return home, to the French motherland. "Heim ins Reich" as Adolf Hitler would later call it.
It is true that Cambrai (Camaricum - earlier it was Bavay or Bavacum) had been the 'civitas Nervorum'. But a civitas should not be
confused with a capital. It was a center of Roman civil administration. The civitas for the Morini (a
people living along the Belgian coast) was in Therouanne (in English that would be Terwane, in Flemish Terwaan), today a small
village near Calais. This civitas was indeed within Morini territory. But Cassel, the former civitas of the Menapians, is very
nearby, no more than 15 km away, and also within Morin territory. The tribe of the Menapians was allegedly (by French historians)
situated in the southwest of modern Holland, almost 100 km to the north! The reality is that neither tribe had a capital as we
understand the word today.
I think that Bavacum was Germanic speaking during the bronze age and that the place-name is identical to 'Bevekom' (beaver-pool), an existing village near Brussels. At the time of the arrival of Caesar, the village had become Gaulish-speaking, but still lay within Nervian territory. As the Gauls very early on gave clear signals that they liked the Roman Empire, the village was chosen as Nervian civitas.