Arthurian Age Maps Collection

There is a lot of change to political boundaries in Britain in the The Arthurian Age. This page offers our bests guesses to the boundaries of Arthurian Britain maps. Below you will find sections devoted to time periods leading up to and through the Arthurian Age, which is roughly the fifth century, with some overlap into the fourth and sixth centuries. Feel free to contact me with questions, comments, etc. It will take some time to complete this page.

“Celtic” Britain prior to Roman Invasion of 43 AD

The British Isles were inhabited by Celtic speaking people who identified with their tribes and did not see themselves as “British, “Irish”, “Picts”, or “Celts”. The tribes of Ireland spoke a different Celtic language than those of Britain. The Picts spoke a language that was very similar to the Britons, and the Celtic language of the Britons seems to have been very similar to that of the Celts of Gaul (France).

This is roughly what Caesar would have found when he invaded in 55 and 54 BC.

Roman Britannia

Roman Britain to 212 AD

Roman Britain from 43 AD to about 212 AD was a single province, Britannia. The Emperor Severus or his son and successor, Caracalla, divided Britannia into two provinces, Britannia Superior (being closer to Rome) and Britannia Inferior.

Roman Britain Divided Again

Roman Britain Provinces 300 AD

Around the year 300 AD, the Emperor Diocletian divided Britain again into a diocese of four provinces under the direction of a vicarius. The specific borders are in dispute, but I find the theories of Keith Fitzpatrick-Matthews to be insightful and compelling, and these are his maps (edited for different eras).

The Last Days of Roman Britain

Arthurian Britain Maps: Roman Britain after 375 AD

Around the year 375, it appears the province of Britannia Secunda was divided to create a fifth province, Valentia. According to Keith Fitzpatrick-Matthews:

In the Late Roman system, the uppermost tier of government was controlled by the Praetorian Prefect of a region (in our instance, of the Gauls, which were divided into three Dioceses: Hispaniae, Septem Prouinciae and Britanniae. Each Diocese was under the care of a Vicarius, who was in charge of the provinces, of which there were five in Britain: Maxima Caesariensis and Valentia were each under the charge of a Consularis, while Britannia Prima, Britannia Secunda and Flauia Caesariensis were under the charge of a Praeses.

Keith Fitzpatrick-Matthews

We know from the Acta of the Council of Arles in 314 that there were four representatives from Britain, presumably from each province. They came from York, Cirencester, Lincoln and (probably) London (the text is corrupt at that point), so we know the various capitals.

A Consularis was a higher ranking official than a Praeses, so they would be based in important towns. Valentia was in the north, and Eburacum (Ebrauc / York) was a capital in the northern provinces, so this suggests that Valentia would be in the northeast. Carlisle would likely have been the capital of a lesser status Praeses for what remained of Secunda. Maxima Caesariensis also had a Consularis governor, so London would have been that capital. We know that Cirencester was capital of Prima, and Lincoln was the most important city in the province of Flavia.

Independent Britain: The Arthurian Age

At the dawn of the Fifth Century A.D., Rome, crumbling under barbarian attacks and internal conflicts, was unable to defend Britain against devastating raids from Pictish, Irish and Germanic tribes. In 410 A.D., when the Britons’ requests for aid were turned down, the Britons revolted, expelled Rome’s magistrates and:

“rejected Roman law, reverted to their native customs, and armed themselves to ensure their own safety.”

Zosimus, late Fifth Century

Calling this era the “Dark Ages” is only valid in the sense that we have very little recorded information from that time. There is little agreement on how to interpret the information, so the Arthurian Britain Maps that follow are very speculative. They are based on the scant clues gleaned from earlier Roman and later Medieval records, archaeology, linguistics, and other disciplines to develop the most plausible view of this era possible.

Arthurian Britain Maps 430 AD

About the year 430 AD, Britain has been independent for about a generation. In that time, fissures in the Roman provincial system began to result in the formation of new kingdoms, splitting off from the core of Roman Britain, which tries to maintain the systems Rome had instituted.

Dumnein appears to have been a powerful entity and likely was one of the first to break away due to power rivalries within Britannia Prima. Demetia was ruled by the descendants of Irish immigrants likely given lands during the later Roman era in order to stop further Irish raids. Their near-autonomous status became official soon after 410. Gwynedd was settled by Britons who migrated to the region from Manau Gododdin (near Edinburgh) to defend that region from Irish raiders. The northern kingdoms, never fully integrated with the southern, are split between the sons and grandsons of Coel Hen, the last Roman Dux Britanniarum. Britannia Secunda becomes Rheged, northeast Valentia becomes Berneich, and what is left of Valentia is named after its capital, Ebrauc (York).

Maxima Caesariensis, Flavia Caesariensis and the remnants of Britannia Prima attempt to maintain the Roman system. They form a council of rulers or kings, and elect a high king over the council. The first high king is Vortigern.