In case you were interested Pharaoh rameses, the area you have marked as British and Belgic is archaeologically unsound (as is quite a lot of the map if I am brutally honest).

Within the British area you have highlighted you cover the (at least in the 1st century BC/AD) territories of the Atrebates, Regni, Cantiaci, Catuvellauni, Trinovantes and Iceni. Of these the Atrebates and likely the Regni were Belgic, at least in the origin of their noble classes. The Cantiaci may also have been Belgic, but the jury is out on that. The Catuvellauni and Trinovantes were British tribes who practiced what is known as the Aylesford-Swarling culture, a cremation rite similar to that employed in contemporary northern Gaul by the Belgic tribes BUT not Belgic as it is post-Cesarean and lacks weapons. The Iceni were culturally separate; they were rather into their torques at this time. All of these tribes minted their own distinct gold coinage which was based upon an original type introduced from Gaul (itself based on Macedonian gold staters issued by Phillip II) in c.150BC. Politically the Trinovantes appear to have been conquered or subjugated by the Catuvellauni whilst, at least on the evidence from coinage, the Iceni were linked in some way to the Catuvellauni. The Atrebates were opposed to the Catuvellauni and the Regni were a pagus of the Atrebates who split from them in the 1st century AD.

On the continent the area you have coloured is known as the Cisrehennian German lands (Germans this side of the Rhine). These tribes are the Nervii and Eburones. Their material culture and settlement pattern was not La Tene, but more closely related to the Jastorf culture of Germany. To the south, in the lands you have coloured Aedui, you have two regions; Suessiones-Remi and "Belgium". The first of these was, as the name suggests, the land of the Suessiones and Remi tribes, two pagi joined into a single civitate by 58BC if not earlier. "Belgium" is the land of the true Belgae, as evidenced by the presence of Fécamp style fortifications, a particular type of sanctuary, distinct burial practices and some critical reading of De Bello Gallico. The true Belgians were the Atrebates, Bellovaci, Ambiani, Velocases and Cantii.