forts in the Roman
Notitia Dignitatum. Pevensey Castle or
Anderitum is the third fort on the third row down.
Bodleian Library, Oxford The fort's construction has been dated to around 290, based on the
dating of wooden piles which were found underpinning the Roman walls in an excavation carried out in 1994. Other Saxon Shore forts were built or reconstructed around this time as part of a systematic programme of improvements to the coastal defences of Roman Britain. It is likely that
Anderitum was built to defend Roman Britain from Rome itself.
Carausius, a Roman general who commanded the
Classis Britannica (the Roman fleet based in the English Channel), revolted against Rome in 286 and declared himself emperor of Britain and northern
Gaul. He was assassinated in 293 by his treasurer,
Allectus, who was himself killed in 296 when the Roman emperor
Constantius Chlorus invaded Britain to overthrow the usurper. Coins of both Carausius and Allectus have been discovered buried in the foundations of the fort's walls. A later coin of 330–335 was found under a tower in the 1930s, suggesting that the fort may have undergone a major repair or reconstruction around that time. The usurpers (or breakaway rulers) had inherited an existing system of coastal defence – the earlier Saxon Shore forts – and may have decided to augment it with the construction of Pevensey Castle and its close contemporary,
Portus Adurni (Portchester Castle). Anderitum appears to have been a key link in the Saxon Shore forts, which extended from Hampshire to Norfolk and may have been connected by intermediate watchtowers. The
Notitia Dignitatum mentions a fleet that was presumably based there, the
Classis Anderidaensis. It would probably have acted in coordination with naval units based on the other side of the Channel to intercept pirate ships passing through. Like the other Saxon Shore forts, Anderitum's position at a strategic harbour would have enabled the Romans to control access to the shoreline and prevent invaders from penetrating inland. It was linked by a road built in the late Roman period, probably at the same time as the fort. ==Construction==