Dumnonia until they submitted to the See of Canterbury in the mid-9th century. Parish organisation was a later development of fully Normanised times. Around AD 55, the Romans established a legionary fortress at "Isca Dumnoniorum", modern Exeter, but west of Exeter the area remained largely un-Romanized. Most of Dumnonia is notable for its lack of a villa system, though there were substantial numbers south of Bath and around Ilchester, and for its many settlements that have survived from the Romano-British period. As in other Brythonic areas, Iron Age hillforts, such as Hembury and Cadbury Castle, were refortified in post-Roman times for
Isca Dumnoniorum building in the fortress not of timber was a stone-built military bathhouse. The water for the bathhouse was supplied by a natural spring via an aqueduct which entered the fortress through the rear gate (). The excavations revealed the hot room () and part of the warm room (). The bathhouse was also supplied with an external exercise yard (), one corner of which was a cockfighting pit. The legion had formed part of the Claudian invasion of Britain in 43, under the command of the future emperor Vespasian. Vespasian led campaigns against both the Durotriges and Dumnonii. The presence