Unique among the territories of the Western Roman Empire in the 5th century, Britain succeeded in holding back and even reversing the tide of Germanic conquest for nearly two centuries. This was an age of heroes… It was the Age of Arthur!

This is the fifteenth-part of our discussion of Britain in the 5th though the mid-6th Century A.D. It is a fascinating period, with the Classical civilization of Greece and Rome giving way to the Germanic “Dark Ages”; the sunset of Celtic-Roman culture in Britain.

(Read Part Fourteen here. Or start from the beginning, with Part One!)


Continuing on, we are attempting to piece-together a hypothetical career of Arthur, the historical basis for the legendary king. At present, we are drawing upon the work of the 9th century Welsh monk, Nennius. In chapter 56 of his Historia Brittonum (c. 830), he discusses twelve battles fought and won by Arthur as war leader (dux bellorum) among the kings of the Romano-Britons in their wars against the Anglo-Saxons:

At that time, the Saxons grew strong by virtue of their large number and increased in power in Britain. Hengist having died, however, his son Octha crossed from the northern part of Britain to the kingdom of Kent and from him are descended the kings of Kent. Then Arthur along with the kings of Britain fought against them in those days, but Arthur himself was the military commander [“dux bellorum”]. His first battle was at the mouth of the river which is called Glein. His second, third, fourth, and fifth battles were above another river which is called Dubglas and is in the region of Linnuis. The sixth battle was above the river which is called Bassas. The seventh battle was in the forest of Celidon, that is Cat Coit Celidon. The eighth battle was at the fortress of Guinnion, in which Arthur carried the image of holy Mary ever virgin on his shoulders; and the pagans were put to flight on that day. And through the power of our Lord Jesus Christ and through the power of the blessed Virgin Mary his mother there was great slaughter among them. The ninth battle was waged in the City of the Legion. The tenth battle was waged on the banks of a river which is called Tribruit. The eleventh battle was fought on the mountain which is called Agnet. The twelfth battle was on Mount Badon in which there fell in one day 960 men from one charge by Arthur; and no one struck them down except Arthur himself, and in all the wars he emerged as victor. And while they were being defeated in all the battles, they were seeking assistance from Germany and their numbers were being augmented many times over without interruption. And they brought over kings from Germany that they might reign over them in Britain, right down to the time in which Ida reigned, who was son of Eobba. He was the first king in Bernicia, i.e., in Berneich.

First, it must be remembered that though he clearly drew on Gildas, a near-contemporary of  Arthur’s, and perhaps other Welsh sources, Nennius wrote centuries after the events he purports to chronicle. At best, we must take Nennius with a grain of salt. However, for purposes of constructing this hypothetical narrative, he is a useful roadmap.

Our discussion to date takes us to Arthur’s ninth battle; which Nennius claims  took place at “the City of the Legion”.

1513311.jpgAttempts to identify this location has (not surprisingly) caused controversy.

Several places in post-Roman Britain could be termed “the City of the Legion”; if having served as the fortress-base of a Roman legion suffices to give it such a sobriquet. York (Roman Eburacum) was home to both the Legio IX Hispana (till about 120 AD) and the Legio VI Victrix thereafter. Chester (Deva), at the northeast approach to Wales, was home to the Legion XX Valeria Victrix throughout most of the Roman occupation. In southeast Wales, in the territory of the Silures tribe, Isca Silurum/Caerleon-on-Usk (also called Isca Augusta) on the River Usk was home to the Legion II Augusta till at least 300 AD. However, this legion was moved sometime in the 4th century to Richborough Castle (Roman Rutupiae), assigned to the “Saxon Shore” garrisons. Finally, Wroxeter (Roman Viroconium Cornoviorum), was home for a time to both the Legio XX Valeria Victrix and the Legio XIV Gemina Martia Victrix.

There are many theories as to which of these is the correct location for Nennius’ battle. Of these possible locales, Chester and Caerleon are the most-often cited; and Geoffrey of Monmouth named Caerleon-on-Usk as the site.

An interesting (and original) theory was proposed by Nikolai Tolstoy: Exeter/ Isca Dumnoniorum, as a follow-up of the fight at Land’s End. In this scenario, after his defeat at Caer Guidn, Cerdic and his remaining Saxons take ship and sail for home, the marshes around Southampton. In route, they attack and (improbably) seize Exeter. Arthur, pursing by land, arrives later to expel Cerdic in this, the ninth battle.

However logical from a military-theorist standpoint, creating a neat campaign narrative (see Part Fourteen, the Battle of Guinnion Fort), this theory suffers from one main deficiency: Exeter/Isca Dumnoniorum was never home to a Roman legion. So how can it be termed “the City of the Legion”?

1513315.jpg Isca Dumnoniorum is an attractive possibility for the battle of the “City of the Legions”, tying in with Land’s End as part of a continuous campaign against Cerdic’s seaborne raids. Unfortunately, it was never the base for a Roman legion.

Carlisle/Luguvalium, at the west end of Hadrian’s Wall, was home to legionary detachments at various times in its history, and has been named by recent scholars attempting to make Arthur simply a regional champion, and to place all of his battles in the Old North (Hen Ogledd). But, like all such attempts, is unconvincing and seems artificial.  Carlisle was never truly a “City of the Legion”, in the sense of having a permanent Legionary garrison.

Richborough Castle/Rutupiae can be eliminated from contention, in that it was deep in Saxon/Jute territory by this period. It is unlikely that a British Army would have penetrated successfully so deeply into enemy lands without first being challenged to battle further west; though a deep raid by Arthur’s swift-moving mounted combrogi  could have theoretically penetrated that far into “enemy territory”.

York/Eburacum certainly fits the bill as a legion home; and as such must be considered a possible contender for this battle site. Could the Angles or Saxons have landed north of the Humber again, threatening Ebrauc? Certainly a possibility.

Chester/Deva is a popular candidate for the  “City of the Legion”. A battle was indeed fought here in 615/616, between the Angles of Northumbria and the Welsh. Some scholars suggest that Nennius confused or deliberately assigned this later battle to Arthur’s time. If it was in fact a battle of Arthur’s, separate-and-aside from the 7th century battle, then the location raises questions as to who the Briton’s enemies may have been. This was rather far west of the known “Eastern Front”, the line of demarcation between Anglo-Saxon and British lands.

The same question applies to a battle at Caerleon-on-Usk, the site identified by Geoffrey of Monmouth. This was a major fortress/town in the heart of the British petty-kingdom of Gwent (south Wales); and as far as we know, not subject to attack by foreign enemy.

Perhaps a rival leader or coalition formed against Arthur, as has been suggested occurred in the north with Caw in 509. But no source suggests such discord among the British at this early date.

However, about this time in history an event occurred in Gwent that provides a possible (if unlikely) explanatory hypothesis. It involves perhaps the former character tentatively identified in previous installments (and my Morrison) as a Visigoth fleet commander, granted land in west Cornwall: Theodoric.

In the late 4th century, an Irish group known as the Déisi Muman settled (or were allowed to settle) in Demetia/Dyfed, southwest Wales.  The term déisi is virtually interchangeable with another Old Irish term, Aithechthúatha (meaning “vassal communities”, or “tributary peoples”). It had been suggested that this term might be the origin of the barbarian raiders known in late Roman history as the Attacotti. These people raped Roman Britain in the 360s; and after order was restored, some were taken into the Roman army as auxilia, as attested to in the Notitia Dignitatum.

1513329.jpg Dark Ages Irish warriors. In the Age of Arthur, Gaelic raiders were called “Scotti”.

One suggestion is that this group was granted Demetia/Dyfed by the Roman Governor/Imperial Pretender, Magnus Maximus (Macsen Wledig in Welsh chronicles). Settling allied or defeated barbarian tribes along unstable or vulnerable frontiers was a common Roman practice in the Late Empire; so this is certainly plausible.

Throughout the 5th and into the early 6th centuries, Irish/Scotti raiders had settled in various parts of western Britain. Then, local accounts indicate that Theodosius (or Tewdric, as he was known in Welsh chronicles) campaigned to drive the Irish out of both western Cornwall and southern Wales. In doing so, he placed Aircol Lawhir (“Longhand”, whose Latinized name was Agricola) on the throne of Demetia/Dyfed; and took for himself the kingdom of Gwent.

Morris and Castleden both floated the hypothesis that Tewdric of Gwent is one-in-the-same as the Visigoth admiral, Theodosius; granted land in Cornwall by Ambrosius or Arthur, as discussed here in an earlier installment. With this land grant came a mandate and authority to patrol the southwestern coasts; and to root out existing and prevent further Irish incursions into Britain.

Returning to our narrative, and attempting to develop a hypothesis for Nennius’ ninth battle,  at the “City of the Legion”:

In 511 Arthur and the sub-kings of western Cornwall repel Cerdic’s raid at the “white fort”, Guinnion, identified in this hypothesis as Lands End. This was on the doorstep of Theodosius the Visigoth’s holdings; and it is impossible that he would not have been among the nine “princes” who fought against the invaders under Arthur’s standard; and feasted with him afterward at Lanyon Quoit!

Perhaps immediately following this victory, or perhaps in the next year’s campaign, Theodosius/Tewdric sails across the Môr Hafren, the “Severn Sea” (Bristol Channel) to Wales; to oust the Déisi and place a scion of the old British dynasty of Dyfed, Aircol Longhand. Afterwards, he moved east into Gwent. There, he is joined by Arthur in battle at Caerleon, where Arthur aides him in seizing the throne.

But in this hypothesis, against whom do they battle?

A possible clue is found in monkish chronicles from later centuries; which talk of an Irish expedition led by Fingar of Gwinnear, son of the Irish King Clyto. Arriving at Hayle, Cornwall, with 700 warriors, they are attacked by Theodosius and repelled. But to where? Did they return to Ireland? Or, perhaps, cross the narrow Severn to land in Gwent?

Gwent at approximately this time was experiencing dynastic problems, and fragmenting into ever smaller sub-kingdoms. Could these Irish under Fingar (or a successor, if he was killed in the earlier fighting  in Cornwall) have attempted to fish in Gwent’s troubled waters, taking advantage of Gwent’s weakened condition?

In this hypothetical scenario, perhaps Theodosius’ campaign in neighboring Dyfed followed close on the repelling of Fingar’s Irishmen; following them across the Severn. In the course of dealing with this Irish threat, Theodosius settles Aircol Longhand on the throne of Demetia/Dyfed.

1513320.jpg South Wales, possible scene of action leading to Arthur’s ninth battle.

At Caerleon, the City of the Legion, Arthur joins his ally Theodosius in crushing Fingar’s Irish. Needing a strong ally to secure south Wales, Arthur grants Theodosius a sub-kingdom in the western portion of Gwent, Glywysing. This sub-kingdom names Tewdric as one of its early kings; though the genealogical data in the various monkish chronicles give conflicting dates for his reign.

According to one of these monkish chronicles, the Book of Llan Dav, Theodosius/Tewdric later resigned the kingship of Glywysing in favor of his son, Meurig; to become a hermit/monk! He was later made a Christian saint (St. Tewdric). However, this may be a garbling of disjointed local accounts. It is even possible under this scenario that Theodoric placed his son on the throne of Glywysing in south Wales; and returned to his lands in Cornwall.

Theodosius/Tewdric ended his life, according to the same sources, in battle beside his son; repelling a Saxon attack. He died victorious, a great end for an old warrior. If he was indeed a Visigoth, as Morris suggested, then he led a storied life indeed.  He was buried at Mathern, near Chepstow, in the church dedicated to him.


Two views of Caerleon-on-Usk: (Top) Artists image of Roman Isca Silurum. (Below) Caerleon today. Note the outline of the ancient Roman ramparts and amphitheater in the lower left quarter of the picture.



This entry was posted in Uncategorized. Bookmark the permalink.


  1. ritaroberts says:

    Fascinating post Barry. But Oh, so many questions Will we ever know the truth. ?

  2. George S says:

    Hi Barry ! Can I expect next chapter as a Christmas gift ? I have to translate it for a greek military history page in facebook cause some friends aren’t english speakers and were complaining ! So I started with the previous because of public demand 🙂 Your name is always mentioned on the top and you and your site have already earned many fans and friends in Greece !!!

  3. George S says:

    In greek ! It’s easier for our members who aren’t english speakers. Others who can read english, are visiting your page. Among others, you re posting excellent articles about greek history and we are grateful Barry

  4. Pingback: THE AGE OF ARTHUR, PART SIXTEEN: REVOLT IN THE NORTH | The Deadliest Blogger: Military History Page

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s