Was Ambrosius Aurelianus the Real King Arthur?

Ambrosius Aurelianus was a historical leader active in Britain in the fifth century. He was a prominent figure and some scholars identify him as the real King Arthur.

Dec 3, 2023By Caleb Howells, BA Doctrines and Methodology of Education

ambrosius aurelianus real king arthur


The Arthurian legends contain an extensive mixture of fact and legend. With the few contemporary sources we have, we can discern the historical truth to a certain degree. One prominent figure who features in the Arthurian legends is Aurelius Ambrosius. Not only was he a real person, but he had a major role in the historical events of fifth-century Britain. Without him, the progress of the Anglo-Saxon conquest of Britain may have looked very different. Some scholars have even argued that he can be identified as the real King Arthur.


The Real King Arthur? What Do We Know About Ambrosius Aurelianus

gildas de excidio folio manuscript
Folio from one of the earliest surviving copies of De Excidio, by Gildas, 10th century, via the British Library, London


The primary source of information about Ambrosius Aurelianus comes from De Excidio, a text written at some point in the sixth century by a monk named Gildas. Although he was not an exact contemporary of Ambrosius, he was not writing too long after his era. Therefore, scholars generally do not treat his comments with suspicion. Unfortunately, Gildas tells us very little about Ambrosius. He discusses him in a passage about the Saxon wars. He explains that the Saxons had engaged in severe attacks on the Britons, causing many of them to flee. They could apparently offer no effective resistance against their attackers.


But then, Ambrosius Aurelianus became the military leader of the Britons and engaged in an effective counter-offence against the Saxons. From that time on, the Britons and the Saxons fought against each other fairly evenly. Sometimes the Britons were victorious, and sometimes the Saxons were victorious. This continued until the Battle of Badon, which was a decisive victory for the Britons.


justinian mosaic san vitale
Mosaic of Emperor Justinian I wearing Tyrian purple, Church of San Vitale, Ravenna, Italy, sixth century


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Gildas does not tell us whether or not Ambrosius was a king. He could have just been a military commander. Later tradition does call him a king, though, and there is nothing in Gildas’ words that makes that unlikely or improbable. He tells us that Ambrosius’ parents had “worn the purple,” but that they had died during the strife of that era.


The reference to them wearing the purple has been interpreted in a variety of ways. It almost certainly means that they had a prominent position of some sort. What exactly this was, we do not know. Purple was the imperial color. On this basis, it has been suggested that Ambrosius may have been the son of an otherwise unknown emperor in Britain, established after the end of Roman rule. But purple was also used by the consuls, and even by military officers. Could his parents have been consuls from the continent? Or might they have been Brittonic consuls, just as other territories that were formerly in the Roman Empire established their own consulships? We simply do not know.


Ambrosius in Later Historical Sources

historia brittonum folio real king arthur
Historia Brittonum, folio 1, via the British Library, London


When it comes to investigating the real King Arthur and the Arthurian legends in general, two later sources are particularly useful. One is the work of Bede, an English writer of the eighth century. The second is the ninth-century Historia Brittonum, usually attributed (perhaps falsely) to Nennius. Most of Bede’s information is repeated virtually verbatim from Gildas, but one new piece of information he provides is related to when Ambrosius lived. He explicitly dates his career to the reign of Emperor Zeno, who ruled from the mid 470s to 491.


The Historia Brittonum is not viewed as a particularly reliable historical source, primarily due to its late date. However, it is a valuable record given the paucity of other early sources available. According to this, Ambrosius was a younger contemporary of Vortigern, possibly even a child at the start of the latter’s reign. All the best evidence supports the Historia Brittonum’s date of 425 for the start of Vortigern’s reign, so that would place Ambrosius’ birth in approximately 420. This is arguably consistent with Bede’s date for Ambrosius’ career.


Arguments in Favor of Ambrosius Being the Real King Arthur

real king arthur battle illustration
Illustration of King Arthur in battle, 13th century, via pocketmags.com


With these fundamental facts out of the way, what about the theory that Ambrosius Aurelianus was actually the real King Arthur? What is the basis for this theory? Essentially, the basis is the fact that Arthur’s most important victory against the Saxons was said to have been the Battle of Badon. This claim is found as early as the Historia Brittonum itself, and it is repeated in all subsequent records about the battle.


Therefore, the basic idea used by many researchers is that the real King Arthur is simply the person who led the Britons at Badon. Gildas’ description of that event is used to support the conclusion that Ambrosius was the one who led the Britons at that battle. Recall that he described the Britons fighting under Ambrosius against the Saxons, and that the back-and-forth between them eventually culminated in the Battle of Badon. He does not explicitly say that this final battle occurred decades after Ambrosius started to lead the Britons. This has opened the way for some to conclude that he was still leading the Britons at that time. Thus, this would indicate that Ambrosius himself was the real King Arthur.


anglo saxon chronicle folio manuscript
Anglo-Saxon Chronicle folio 37r, 17th century, via the British Library, London


A related argument is based on the fact that Gildas never mentions Arthur at all. Given that the portion of history covered by his account encompasses the era of Arthur’s supposed reign, this seems rather suspicious. Many scholars take this as an indication that Arthur never existed at all. Furthermore, Arthur is not mentioned by Bede, nor by the tenth-century Anglo-Saxon Chronicle. In view of this lack of direct evidence for his existence, many scholars feel that Arthur cannot have existed.


Yet, it is self-evident that legends of Arthur do exist. So, how did those legends get their start? One line of thought is that Arthur started off as a folkloric figure who was gradually historicized. However, others feel that he must have come from a historical figure of the period, who then later acquired the name “Arthur” somehow. Since Ambrosius is known to have really existed and his activities (even excluding Badon) at least broadly match Arthur’s, he is an obvious choice.


Problems with the Theory that Ambrosius was the Real King Arthur

real king arthur fighting saxons rochefoucauld grail manuscript
Illustration of King Arthur fighting the Saxons from the Rochefoucauld Grail manuscript, 14th century, via the Independent


This logic is simple enough. But does it actually stand up to scrutiny? In reality, there are a few key issues with it. For one thing, there is no reason why Ambrosius and Arthur could not both have been involved in the battle. Consider the fact that in the earliest references to Arthur, there is no mention of him being a king. This leads many scholars to conclude that — if he was real — Arthur was a military commander, not a king. If Ambrosius was a king (and he is explicitly called “high king” in the Historia Brittonum), then Arthur would have been a commander in his service. Thus, even if Ambrosius really was still leading the Britons at the time of the Battle of Badon, this would not necessarily make him the real King Arthur. So on this basis, we see that the logic that the leader at Badon must have been the real King Arthur simply does not stand up to scrutiny. It could be correct, but there is no guarantee.


annales cambriae folio f190r
Annales Cambriae in the Harleian MS 3859, folio 190r, via the British Library, London


What about the lack of evidence for Arthur’s existence? Really, this is not significant. Gildas mentions almost no one at all throughout his entire work (apart from the five living kings to whom he directs some comments). He was writing a sermon, not a history. Bede took his information almost entirely from Gildas, so naturally, Ambrosius is the only British leader in that period mentioned by him, excluding the Saxon ally Vortigern. The Anglo-Saxon Chronicle does not even mention Ambrosius, yet his historicity is not in doubt.


More significantly, there is very good reason to believe that Ambrosius cannot have been the leader at Badon and thus the real King Arthur. As we saw earlier, he was likely born around 420. The Battle of Badon, meanwhile, is dated to 516 in the Annales Cambriae. The Historia Brittonum seems to imply an even later date, apparently placing Badon in the era of Ida of Bernicia. In either case, Ambrosius would have been much too old to be participating in any battles by that time. This would preclude him from having been the real King Arthur.


Was Ambrosius Aurelianus the Real King Arthur?

aurelius ambrosius historia regum britanniae real king arthur
Depiction of Aurelius Ambrosius from a manuscript of Historia Regum Britanniae, 15th century, Wales, via Wikimedia Commons


In summary, Ambrosius Aurelianus was a historical leader of the Britons in fifth-century Britain, during a time of intense turmoil. He helped the Britons to recover from the devastating attacks of the Saxons and prevented them from being completely overwhelmed. From Gildas, we know that he was the son of prominent parents, although we do not know exactly what position they had. Based on the information from Bede and the Historia Brittonum, we can conclude that Ambrosius was likely born in about 420. The main part of his career, in which he campaigned against the Saxons, occurred somewhere between c. 475 and 491. Some scholars try to argue that he was the real King Arthur. This is based on the perceived implication by Gildas that Ambrosius was the victor at Badon. However, this is a very shaky foundation on which to base a theory. The dating of the Battle of Badon by other records places it well into the sixth century, which would make it impossible for Ambrosius to have been the leader. This argues strongly against identifying him as the real King Arthur.

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By Caleb HowellsBA Doctrines and Methodology of EducationCaleb is a published history author with a strong interest in ancient Britain and the Mediterranean world. He holds a BA in the Doctrines and Methodology of Education from USILACS. He is the author of "King Arthur: The Man Who Conquered Europe" and "The Trojan Kings of Britain: Myth or History?". Caleb enjoys learning about history in general, but he especially loves investigating myths and legends and seeing how they might be explained by historical events and individuals.