by Peter Kessler, 1 April 1999. Updated 16
The well-known date of Britain's final official
break from Rome is AD 410, but by that stage Roman Britannia had
mostly been fighting its own battles for at least thirty years
with only occasional support from Rome itself. It was forced to
look after its own interests in the face of increasing numbers of
barbarian raids; from the Picts to the north, the Scotti (Irish)
to the west, and from various Teutonic tribes that were raiding
the to the south and east of the country.
There had been frequent barbarian raids throughout
the latter part of the fourth century in Britain. The 'Barbarian
Conspiracy' of 367 was a threefold attack by Teutons from across
the North Sea, and Picts and Scotti from the north and west. It's
impossible to know how well coordinated these attacks were - or
whether they were coordinated at all. The attackers kept no records
of their own at this time and even Roman records of this period are
sketchy as the imperial system was gradually breaking down.
The next crisis faced by Britain came in 383 when
the military commander, Magnus Maximus, realised that Roman power
in the region was becoming increasingly toothless. He made his own
claim for imperial power, supported by the army. His death in 388
deprived the island of the greatest part of its military strength,
although the reorganisations usually attributed to him shored up
the north and the western coasts of Britain. However, there appears
to have been almost continual warfare against the Picts during this
Around 398, Britain apparently had to be rescued
from her barbarian foes, this time by the most powerful general
of the Western Roman empire, Stilicho. Stilicho's intervention was
the last occasion on which a major expedition was mounted against
the enemies of Britain.
Soon after the situation had been retrieved, Roman
forces on the island were further reduced to save Italy from invading
Goths. By 406, Britain's military strength had largely been drained
away, and the following decade saw the process completed.
In 406 a vast army of barbarians crossed the frozen
Rhine and began advancing westwards towards the Channel coast. It
began to appear as though Britain could be invaded.
Earlier in the same year, the army in Britain had
already elevated an unknown soldier, Marcus, to supreme power. He
did not last long, being supplanted at the time of the barbarian
advance through Gaul by Gratian, an urban magistrate (magistratum).
Gratian survived only four months, and the army's next choice fell
on a soldier, Constantine, who challenged Roman authority in Gaul,
creating a prefecture at Arles from which to rule as Emperor
Constantine had, in 407 removed at least something
of Britain's remaining trained forces only to be killed in 411 at
Arles. The troops never returned but instead may largely have
settled in Armorica, paving the way for later British migrations
In 408/409, Britain was subjected to a large-scale
barbarian invasion, probably by Saxons with Anglian support.
The British civitates - the urban centres
- managed to defend themselves and by 409 had quelled the attack,
although details of how they did this are not available. It is
possible that many of the surviving defeated Saxons and Angles were
employed as foederati - mercenary troops - to garrison the
Saxon Shore (the east coast) and protect it from further attacks.
Although this was established Roman practise, and was undoubtedly in
use before this time, this action would help to explain the large
number of Teutonic sites along Britain's east coast that are evident
from before the so-called Adventus Saxonum in 450.
In 410, the feeble Emperor Honorius informed the
internal government of Britain that it would have to look after its
own defence, implying that this would be a permanent arrangement.
During what was either a revolt of peasants and slaves in Britain in
409 to mirror either the popular uprising of the oppressed classes
in Armorica (Brittany), or at the tail end of the barbarian invasion,
the Romano-British governor had appealed for imperial help.
In the face of this abandonment by Rome (although
there is much more to this story and its background - see The
End of Roman Britain), the defence of Britain was left to the
western and northern kingdoms and whatever remained of the central
government. In the eyes of the traditionalist Celts of the wilder
north and west, the leading figure of this central authority would
probably have fulfilled the traditional role of high king of Britain
- if such a title ever actually existed. To his Romanised peers he
could have been known as emperor of Britain in the Roman fashion,
at least while such a title still meant anything.
Theoretically, Vortigern could have been the first
of these purely internal emperors, with Ambrosius Aurelianus and
Arthur following them (Uther Pendragon is harder to pin down, but
would have governed between Ambrosius and Arthur unless, of course,
he was in reality the same person as Ambrosius, an argument not
within the scope of this feature).
Border client kingdoms
Welsh tradition has long held that Magnus Maximus
arranged the island's defences before undertaking his expedition
abroad to claim the imperial title. Other sources attribute some
of the changes to Vortigern, so a combination of the two is highly
likely. Magnus Maximus, though, clearly seems to have begun the
work and seems likely to have made the greatest number of changes.
What he apparently did was to arrange large defensive areas that
could be governed by client tribes or native Roman officers.
All of these were set up in the militarised zones,
in the west and north, areas that had never been fully Romanised
and which had been under military control for years through several
chains of forts. The borders shown in the map below are mostly
conjectural, but are based on later kingdoms that emerged in these
areas through the inevitable fragmentation that occurred when Celtic
tradition demanded an equal distribution of land between surviving
The south and east, areas far more greatly Romanised,
came under the island's central administration for as long as it
lasted. This explains the proliferation of early independent Celtic
kingdoms in the west and north, while the heart of the Celtic 'Lloegr'
(England) was much slower to fragment and, perhaps because of that,
was a much easier area from which Angles and Saxons could grab
However, kingdoms - or at least small city states -
did emerge in the south and east, mostly towards the end of the
fifth century. Some of these left evidence of their survival, if
not their names. (Details of these can be accessed via the The
Island of Britain. map.)
The solid red that depicts Roman Britain began to
fracture in the late fourth century, while the early
fifth century saw it broken up almost entirely (click
or tap on map to view full sized)
Romans were still being buried in London in the early fifth
Ceretic Guletic, king of Alt Clut
Ceretic was the earliest-known ruler of Alt Clut
(Strathcluaide) in this period, and perhaps the first to be recognised
by Britain's central administration. However, it seems certain that
the kingdom was created in AD 148, and possibly by a descendant of
the last free high king of Britain, Caratacus. This was one of the
'four kingdoms of (Lowland) Scotland' which held the territory between
'proper' Roman Britain and the Pictish (British) north. Most of them
may have maintained Roman client kingdom status for much of their
existence before 409.
Ceretic ruled his territorium from the
location from which the kingdom took its name, a rocky promontory
overlooking the Clyde. This capital became known as the 'Fort of
the Britons', Dun Breaton (and later, Dumbarton). Policing the
western half of the Antonine Wall as a (probable) Roman client
chieftain, Ceretic and his descendants forged a strong but poorly
recorded kingdom which, alone amongst the British kingdoms outside
Cymru, was never successfully conquered by the English. Instead,
after becoming a Pictish/Scottish satellite state in the ninth
century, it was fully merged within Scotland in the eleventh
Although Cunedda Wledig originated from the
westernmost part of this region around the start of the Firth of
Forth if, as per tradition, he was relocated by Magnus Maximus then
he would have been in North Wales by 383. The first known ruler of
Guotodin is Lot Lwyddog, who reigned around the end of the fifth
century - before that there seems to be little information on this
northern tribe and it is possible that the Votadini chieftains,
late in accepting the benefits of Roman civilisation, were also
late to unite and form a single political entity.
Nora Chadwick's The Celts theorises that
Coel Hen and his descendants guarded this eastern end of the Antonine
Wall, in the buffer zone between that and Hadrian's Wall. Could Coel
Hen have commanded, as governor of the militarised zone of northern
Britain, the Votadini chieftains, perhaps dealing directly with one
high-chieftain? It seems highly plausible after the death of Ceneu
ap Coel, Coel Hen's son, that the Votadini (Guotodin), would seek to
emulate the kingdoms being formed by his sons to the south.
As a kingdom, Guotodin may well have been created only by around 470,
with Lot Lwyddog as its first ruler.
Unfortunately, the kingdom never had a stable line
of succession, and after the rulers (a king and a probable sub-king)
were defeated at Catreath around 597, as described in the Gododdin,
the Guotodin were fatally weakened, and their remnants fell in 638
to the Angles of Bernicia.
 In his book, Roman Britain,
Guy de la Bédoyère contests that the mention of Valentia in the
is a transcription error that should instead say that the province
of Maxima Caesariensis had been renamed Valentia, probably at the
same time that London was renamed Augusta, after 367.
Coel Hen, governor of Northern Britain
The capital of late Roman Britain in the north
was Eboracum, later Ebrauc to the British, Eorforwic to the
English, and contorted into York by the Danes. This was the
civitas capital of the Brigantian Britons who, as pre-Roman
Celts, had ruled a huge swathe of central northern England in the
early first century AD and probably before.
Archaeological evidence points to a period of
rebuilding in York at the start of the fifth century, when Coel
Hen was estimated to be at the height of his governorship of the
region. But, formed partly it seems from the Roman military district
of Valentia, the province of Northern Britain covered the whole of
the Roman militarised zone from a line close to the Humber to Hadrian's
Wall and a lesser sphere of influence for some distance beyond it
(perhaps including the Votadini, as mentioned above). 
Quite possibly appointed to his position by the
departing Magnus Maximus, Coel Hen was probably the last Roman-style
dux brittanniarum, and he would have ruled in a very Romanised
fashion. He held the north in a strong protective grip, and guaranteed
that he and his immediate descendants had little trouble from the
Picts to the north. Unfortunately, his descendants divided what was
a very strong single political entity into a patchwork of small
kingdoms that fell one by one to the Angles.
Cunedda Wledig, king of North Wales
The ninth century Historia Brittonum (The
History of Britain, attributed to a certain Nennius) is the
earliest source of Welsh history outside the Lives of the Saints.
It records that a certain Cunedag (Welsh 'Cunedda'), together with eight
of his sons and one grandson, came from Manau Guotodin (near the Firth of
Forth) a hundred and forty-six years before the reign of Maelgwyn, king
of Gwynedd, and that they had expelled the Irish forever from those lands.
This was the primary reason behind the decision to
invite Cunedda to become 'King of North Wales' as he was styled (although
this appellation probably came much later, after his lifetime - he was
never referred to as rex, 'king', in the Historia Brittonum).
Maelgwyn's reign began in 517 so this places Cunedda's migration at 371,
which seems a little early. Magnus Maximus is usually credited with
reorganising the country's defences leading up to his departure in 383,
and it is this date that is more traditionally linked with Cunedda, so
something between 380-383 seems more acceptable for the move.
Cunedda and his people quickly settled in Gwynedd,
carrying out their task of expelling the Irish invaders who had begun
to settle there. The process of 'freeing' North Wales seems to have
lasted a few years, until the only remaining Irish stronghold was on
Ynys Mon (the Isle of Anglesey). Signs of Irish settlement in the area
can still be found opposite Irish Leinster, in the probable origin of
the Lleyn peninsula - the long 'pig's ear' - as its name may contain
Irish Laigin, meaning 'Leinstermen'.
Antonius Donatus Gregorius, king of South
Antonius, also known to Welsh tradition as Anawn
Dynod, was another alleged son of Magnus Maximus, set up in his
own territorium either by his father or shortly after his
departure. The positioning of Demetia, kingdom of the Demetae
Britons, meant that it could protect the south-west coastline from
The South Wales region soon crystallised into the
kingdom of Demetia, later Dyfed, and was made up of two main regions.
The larger part of the territory was Dyfed itself, while Ystrad Towy
(or Towi) made up the eastern third or so. This was conquered around
690 by Ceredigion, but Wales was united under the kings of Gwynedd
in the ninth century, and Dyfed came to form the heart of a united
South Wales after that, with Deheubarth being formed out of this union.
The later kingdom of Brycheiniog also seems (at least partially) to
have formed a division of the South Wales territory.
As a complete opposite of the process going on in
North Wales at the same time, Irish settlement in Demetia was actively
encouraged in the form of inviting the Irish Déisi tribe to settle
there. They seem to have been brought in to act as foederati
on the west coast, keeping the British shores clear of Irish raiders,
an apparently successful policy. In the region, many Irish words are
mixed into the regional dialect, and there is a considerable spread
of memorial stones pointing to Irish influence. The incidence of
Ogham (Irish) symbols, highest in the modern county of Dyfed, is a
crude guide to the settlement of the Déisi. After the British line
of rulers had died out, the Déisi were best placed through intermarriage
to assume the legitimate rule of Dyfed.
Although many later Welsh kings claimed descent
from Magnus Maximus in order to legitimise and enhance their own
status, Owain Finddu has one of the better claims. His territory
seems to have been created or founded to plug a gap between South
Wales and Ewyas (on the western bank of the River Severn).
The kingdom of Cernyw emerged from this under the
control of Owain's son, and was renamed after Owain's great-grandson
as Glywyssing. Even later, in the tenth century, it was again renamed
after one of its most powerful late rulers as Morgannwg, and is
remembered as today's Glamorgan region.
Probably the great-grandnephew of Eudaf Hen
(the Old), former king of Ewyas, Meirchion son of Gwrgant seems
to have been the last ruler of Ewyas. The kingdom was without a
ruler in around 430 so that Vortigern was able to give it to his
eldest son, Vortimer. Vortimer appears to have been able to claim
the area as his inheritance through the maternal line as a great
grandson of Eudaf Hen.
Ewyas as a distinct region seems to date from
at least the late third century. It was situated at the very
centre of what in the mid-fourth century became the Roman civil
administration's province of Britannia Prima, stretching from
Cornubia to North Wales and east to the Gloucester and
Vortigern, king of Pagenses (Powys)
The Pagenses appears to have grown into a recognisable
region and even kingdom only in Vortigern's time, so it is likely he
was drawing upon territory that had previously come under Britain's
central administration. This was part of his powerbase from which he
was able to build his claim to be able to command all of Britain.
Philip Barker's painstaking years of investigation
at Caer Guricon (Urecon, Roman Viroconium, modern Wroxeter), which
was the part-military, part-civil civitas (tribal capital)
of the Cornovii, revealed the construction well into the fifth
century of a large and remarkable timber palace on quasi-Classical
lines. Grandiose in conception, there existed a massive hall with
a linear spread of outbuildings and even, perhaps, shops, all
executed in timber. Once Pengwern had emerged as a separate region
at the end of the sixth century, this became its early capital.
Vortigern's main powerbase seems to have been further
south than Powys. His father may have had connections with Caer Gloui.
Given the later divisions of towns in the area, Caer Baddan and Caer
Ceri could also have formed part of this territory. From the available
evidence it seems likely that, once Vortigern was defeated shortly
after the civil war of the 440s, Ambrosius Aurelianus confirmed the
rule of Vortigern's compliant sons over Powys, Builth, and Gwent, and
took the Gloucester region to form his own powerbase in the south. Is
it possible that the territories of Caer Gloui, Caer Baddan, and Caer
Ceri all formed parts of one administrative region in the mid-fifth
century, and that they were passed onto Ambrosius' descendants, to
finally be conquered by the West Saxons in 577? It seems highly
Vorimorus, king of Dumnonia
The Celtic tribe of the Dumnonii ruled a large kingdom
that covered the whole of the West Country from Somerset onwards. It
probably began to emerge as a distinct region by the beginning of the
fourth century. It had become a fully independent kingdom by the fifth
century, probably by 410.
In this area, scarcely touched by Roman occupation,
the Dumnonian leaders would have exercised a far higher level of
self-rule than many areas of Britain. They controlled a wide swathe
of territory that also comprised the former territory of the Durotriges
and the possible tribe of the Cornovii, in modern Dorset and Cornwall
As well as producing one of the earliest independent
kingdoms south of Hadrian's Wall, Dumnonia was one of the most stable
until the West Saxon territorial gains of the late sixth century,
neither changing its name nor fragmenting in the way of most of Britain's
Celtic kingdoms. It produced a few sub-kingdoms - Glastenning, Cornubia,
and Lyonesse - which were ruled, in the same manner as Gwynedd, under
Dumnonia's overall control, and were mostly later drawn back under
direct rule. Glastenning was the only one not regained in whole, but
this was due to Saxon conquests in the region.
In the remote south-west, the English name, 'Cornwall',
derives directly from its Romano-British label. Its late Romano-British
name, Cornouia, which was Latinised as Cornubia, has survived
as Welsh Cerniw and Cornish Kernow (not to be confused
with the Cernyw of Glywyssing). Cornubia seems to have constituted a
pagus, a Roman subdivision, within the civitas of the
Dumnonii and later, as stated, a sub-kingdom for a time before it was
merged back into Dumnonia as the latter was being reduced by Saxon
View a series of maps showing Dumnonia's
existence between around AD 400 and its final extinction at
the hands of the West Saxons (click or tap on image to read
more on a separate page)
Although the region illustrated on the map above existed
as a late fourth century Roman civil administration province (borders
conjectural but relatively acceptable), some older sources list its name
as Britannia Secunda, and place Flavia Caesariensis as a very small province
in the area of Carlisle in modern Cumbria.
By the late third century the whole south-east region
was governed by the Comes Litoris Saxonici, 'Counts of the Saxon
Shore', with an opposite number of equal rank controlling the north in
the form of Dux Britanniarum, 'Duke of the Britons', the last of
which was probably the Coel Hen (although like Arthur his existence
and role are not fully accepted). The comes was charged with
guarding the entire east and south coast, from the Humber to the Isle
of Wight, from increasingly frequent raids by Saxons and Irish Scotti.
Many of the defended areas were settled with Teutonic
foederati to strengthen native defences there. These forces may
have greatly been increased after the barbarian raid of 408/409, when
the Roman administration was expelled and the Britons had to look after
their own defences. They eventually seem to have sided with mid-fifth
century Teutonic arrivals to form the earliest Saxon and Anglian kingdoms
in these regions.
It seems highly likely (although it is completely
undocumented) that, if the south-eastern Roman provinces survived the
AD 409 expulsion of Roman administration and its uncertain aftermath,
then they probably survived until the middle of the same century. In
that period, over the course of a decade, the country was ravaged by
foederati revolt, plague, civil war, Pictish incursion, and
The Romans were familiar with the Celtic tribal
divisions in the country, and they accommodated this habit in their
own organisational divisions. Britain (England and Wales) is a
relatively small country, but then as now it is still too large
and diverse to administer as a single entity.
Britannia Superior was created by the Romans in
the third century to administratively separate the south of Britain
from Britannia Inferior, the militarised north ('Superior' meaning
'higher' and 'Inferior' meaning 'lower' in the sense of nearer to,
and further from, Rome itself).
A century later, this administrative zone was
further divided to create Britannia Prima (Wales and the West
Country), Flavia Caesariensis, and Maxima Caesariensis. Inis
Vectis (later Ynys Weith) would have come under the control of
this latter region.
Ceint, whilst perhaps administratively still a
part of Maxima Caesariensis in AD 409, seems to have become a
petty kingdom by circa 425.
Further north, the marshes around The Wash seemed
to have regained the ground they had lost under Roman administration.
Second century Roman drainage work, which may have been poorly executed
in the first place, was abandoned during the mid-fourth century
economic slump and was never repaired.