Isca Dumnoniorum settlement there (modern Caerleon) to be distinguished as "Isca Augusta", while the Devonian Isca was called "Isca Dumnoniorum": Usk of the Dumnonians. Exeter began as settlements on a dry ridge ending in a spur overlooking a navigable river teeming with fish, with fertile land nearby. Although there have been no major prehistoric finds, these advantages suggest the site was occupied early. Coins had been discovered from the Hellenistic kingdoms, suggesting the existence of a settlement trading with the Mediterranean as early as . This is disputed however by Prof T P Wiseman who alleges the hoard was not genuine. Following
Isca Augusta the Silures in South Wales who had resisted the Romans’ advance for over a generation. Isca became the headquarters of the Legion II Augusta based in the large fortress of typical legionary "playing-card" shape and built initially with an earth bank and timber palisade. It remained their headquarters until at least 300 AD. The interior was fitted out with the usual array of military buildings: a headquarters building, legate's residence, tribunes' houses, hospital, large bath house, workshops, barrack blocks, granaries and, unusually, a large amphitheatre.. At this time there were 4 legions in Britain out of a total of about