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Gildas the Monk & Maelgwn the Murderer
David H.R. Sims' examines Two Key Sub-Roman Characters

About AD 540, the monk, Gildas, compiled an extensive sermon, De Excidio et Conquest Britanniae1, in which he vehemently denounced the corruption and torpidity of the contemporary British. As exemplars of the current evil, he selected five rulers for especial castigation viz.: Constantine of Dumnonia (murder, adultery), Caninus Aurelius2, (parricide, adultery, general rapine), Vortipor of Dyfed (murder, adultery, incestuous rape), Cynglas of Rhos (seduction of a nun - the widowed sister of his wife) and, at the top of his list, Maelgwn Hir of Gwynedd, whose sins he expounded in the greatest length and detail. Implying that he was merely selecting from a much wider inventory, Gildas alleged that Maelgwn had killed his uncle, the King, in what was essentially a coup d'etat, taken Holy Orders in a fit of remorse, broken them to marry and after some years, murdered his wife and nephew in order to marry the latter's widow, this second marriage being conducted with some pomp and circumstance. It is these murders which form the subject of this essay.

Maelgwn Hir was the great grandson of Cunedda, a chieftain who had migrated with his band to Wales from Manau Gododdin (traditionally) 146 years before Maelgwn came to the throne3. Such was the migrants' success that Cuneddan influence extended over most of North and Central Wales. On the Death of Cunedda's son, Einion Yrth, it appears that the kingdom of greater Gwynedd was divided between his sons, Owain Danwyn (Rhos) and Cadwallon Lawhir (Gwynedd proper). A third son, Einyaw4, received nothing and it might be conjectured that he predeceased Einion. The Harleian MS3859 genealogies note a simple succession of sons; in Rhos, Cynglas followed Owain, and Maelgwn, Cadwallon in Gwynedd. But within this, a murder occurred. Recently, it has been argued that Maelgwn's victim was Owain5 on the basis that since Maelgwn killed his uncle, the King, and as Maelgwn was the son of Cadwallon, the only qualified potential victim would be Owain. However, if this theory is examined in depth, certain weaknesses become apparent.

Now it is clear from Gildas that Maelgwn overturned his uncle in a coup of some violence -' you killed him and nearly the bravest soldiers'... 'after your dreams of rule by force had gone according to plan'6. As there can be no doubt that Maelgwn ruled in Gwynedd, it must be assumed that its control was the subject of his coup. But, since Owain held Rhos, his removal would have little bearing on the future of Gwynedd. It could be argued that on the death of Cadwallon, Gwynedd reverted to the suzerainty of Rhos, leaving Maelgwn disinherited. However, if this were the case, why then did Maelgwn annex only Gwynedd and not Rhos as well. He did not, and the line of Rhos continued to 825AD7. If only to protect his flank, the neutralisation of Cynglas the eddling, should have been an essential part of the plan, but Cynglas survived and flourished to become a ruler sufficiently powerful and corrupt to receive the bitter attention of Gildas. While there is evidence that Cynglas fomented civil war, there is no suggestion of his pursuit of a blood feud, which surely would have followed the assassination of his father. In truth, it is difficult to see any rationale behind Owain as the victim.

There is however, a further, equally valid, reason for dismissing Owain as the potential victim. Gildas actually described the deposed uncle as an 'avunculus'8 to Maelgwn. Specifically, this translates as the brother of Maelgwn's mother. Given that he was the son of Cadwallon, then the kingship is uniquely defined as passing from Cadwallon to his brother-in-law, and this excludes Owain and all other brothers or related kin9. To achieve such a transfer peacefully, Cadwallon would presumably have had to nominate a designated heir, a course fraught with dangers for both of them in the face of a disinherited son and anxious family members, not mention the ambitious brother-in law. From the dates calculated in the appendix and the absence of any known ruler between Cadwallon and Maelgwn, it must be surmised that any intervening reign was of some brevity. It is more likely that the uncle seized the throne. Presumably Gildas would have known this, but he, usually voluble on the subject of tyrants10, remains silent. While these possibilities cannot be ignored, but overall they are hardly compelling.

Finally, there is Cadwallon himself, and any consideration of him in this context introduces the paradox that either he did not rule Gwynedd, or that Maelgwn was not his son. Now the former is known to be correct; therefore the latter statement must be examined. It is generally accepted that many genealogies, and especially their earlier parts, are unreliable. Apart from simple scribal errors such as the interpolation or removal of persons, more sophisticated techniques included the addition of spurious ancestries either real or imagined to increase the prestige of the subject of the genealogy or justify his position. In short, they could easily become vehicles of propaganda11. To complicate matters further, genealogies often suffered confusion with regnal lists. Here familial relationships could be distorted, and in many cases, e.g. Powys12 and Wessex13, the apparently smooth transitions of power seem to mask some unpleasant internecine strife. The Harleian Manuscript exhibits many of these irregularities. There is true genealogy, as where descent is recorded through the distaff side; there are cases where brothers are noted. But there are also ancestries reaching back to the Celtic gods, to the cousin of the Virgin Mary, to various roman officials, and in one case, a whole series of roman emperors are cited as son of - map........map. It must be considered therefore that the Harleian document may not be quite the ancestral list that it seems and that there has been confusion or deliberate inclusion of regnal lists in the manuscript. In which case, the implied father/son relationship need not be regarded as the actual state of their kinship, and therefore, it can be argued that Cadwallon was the victim of Maelgwn's coup. This being so, any ambiguities concerning use of the term avunculus naturally disappear as it would be assumed that Maelgwn was the son of an unnamed daughter off Einion.

If Maelgwn exhibited a naked political ambition in removing his uncle, what were his motives for killing his wife and nephew? Gildas was clear on this point. Maelgwn and his paramour were steeped in sin and their wedding could only be possible through the death of their respective partners. Maelgwn was a strong king. He was a successful king. There is little reason to doubt that he could be ruthless on occasion, or that he possessed an appetite for women, but neither is there any evidence to suggest that he was psychopathic or politically naive, and the deaths of prominent members of the ruling family would certainly have immediate internal consequences. Even if he had become insanely infatuated (and it is fair to assume that he had power to possess any women he wanted), he could have incarcerated or demoted his wife, or exiled his nephew. In short, he had no need to kill them; thus the Gildasian view of unbridled lust lacks credence, and other motives must be sought. Were they perhaps caught in flagrante delicto? This certainly would lead to the demise of the nephew and perhaps the wife as well. But then there is the curious feature of the public marriage that rests ill with the evidence at hand.

To rulers such as Maelgwn, marriage was a complex affair carrying distinct dynastic and political overtones. The Gildasian theory would therefore demand a devotion and public display of affection virtually unique to the age. However, there are also precedents for marriage as a unifying gesture between warring factions, where the victor married the widow of the deposed/defeated/deceased party14, and this might seem to have more credibility. The following scenario is certainly incorrect in absolute detail, but in broadest outline, it would appear to provide an adequate explanation of events.

Nesta, wife of Maelgwn, is the daughter of the exiled Pennine King, Sawyl Penuchel, scion of a family not unused to intrigue. It is becoming increasingly likely that Maelgwn's illegitimate son, Rhun, will succeed his father and with this, her influence is set to diminish considerably, or perhaps, this is already happening. There is however a nephew at court married to Sannan, the daughter of Cyngen Powys. He is ambitious but without any real hope of advancement. Nesta cultivates him, and in passing notes that it would not be the first time that a nephew has overthrown his uncle. Maelgwn discovers the plot and has the conspirators executed. But he is left with a problem since divisions remain between himself and the cowed supporters of Nesta. To unify and cement support, he marries Sannan in a ceremony of some magnitude, which incidentally brings closer ties with Powys.

The scenario receives some support from subsequent events. Eurgain, the daughter of Nesta, eventually married Elidyr of the house of Dumnagual Hen. On the death of Maelgwn, he led an attack on Gwynedd, designed to wrest the crown from Rhun. The invasion, which also initiated a conflict that rumbled on for some years, was defeated and Elidyr killed. While it is true that descent through the bastard line was not common, it seems clear that Rhun was the accepted ruler, and that Eurgain knew it. Therefore it might be argued that their motive was spurious as to the question of legitimacy but was fueled by the twin factors of greed and revenge.

What, then, can be concluded from the foregoing. At one level, it is nearly certain that Maelgwn was guilty of one murder (his uncle) but his involvement in the deaths of his wife and nephew is much less clear. The De Excidio is a biased, bigoted work, but it remains the only document of any contemporary value. If the scenario outlined above has any accuracy, then either, Gildas was unaware of what transpired or he did know but distorted the facts. In either case, it bodes ill for credibility, and while his big, bad, five were hardly candidates for a tea-time visit to a maiden aunt, it might now be questioned whether they were really as evil as they were portrayed. At a different level therefore the essay demonstrates the inherent pitfalls arising from taking Gildas at face value.

Next: Appendix: A Note on Dates


  1. The Gildasian quotes are taken from the translation given in the web site 'The Ruin and Conquest of Britain AD 400 - AD 600' maintained by Howard Wiseman.
  2. The exact identity of Aurelius Caninus is unknown. David Nash Ford has suggested Cyngen Glodrydd, and this would be consistent with the Gildasian addiction to arcane Latin puns. Cynan Garwen, his grandson, would probably be too late for consideration. It has also been suggested that the Latin name is indicative not of wit, but of a dissolute descendant of Ambrosius.
  3. Historia Brittonum.
  4. There is evidence that Einyaw was actually a half brother to Cadwallon, and Einion has been credited with two further sons Llyr and Tegog (Jesus College MS20; The Bulletin of the Board of Celtic Studies 20 (1963); Bartrum, P.C. (1963&7) 'Pedigrees of the Welsh Tribal Patriachs' in National Library of Wales Journal 13 & 15)
  5. Phillips & Keatman. 
  6. Gildas, quoted in Wiseman. 
  7. Annales Cambriae. 
  8. Gildas ('Maelgwn Gwynedd' in Bartrum, P.C. (1993) A Welsh Classical Dictionary.) 
  9. It might be argued that, used loosely, avunculus could refer to any uncle, either paternal or maternal. However Gildas was fastidious to the point of pedantry in his Latin terminology, and it would seem totally at variance with he rest of the work for him to use a word in anything other than an exact sense. 
  10. In the context of those who usurp power or acquire it by dubious means. 
  11. For a simple, accessible discussion of the problems raised by genealogies, see Alcock, or Brooke. 
  12. See the EBK's Glastening: Dynastic Origins.
  13. Brooke. 
  14. King Cnut I of Denmark, England & Norway (995-1035); King Henry VII of England (1457-1509); etc. 


  • Alcock. L., Arthur's Britain, Penguin. 1971.

  • Anon., Annales Cambriae, trans. J. Morris, Phillimore 1980.
  • Brooke. C., The Saxon and Norman Kings. Fontana 1971.
  • Gildas., De Exidio et Conquestu Britanniae.
  • Nennius., Historia Brittonum, trans J. Morris, Phillimore, 1980.
  • Phillips. G. & Keatman. M., King Arthur: The True Story. Century Random house 1992.
  • The relevant pedigrees are those quoted in this site.


    David H.R. Sims 2001. All Rights Reserved.