
In the Arthurian legends, King Arthur has many enemies. However, the one enemy who is actually able to bring down his kingdom is his own nephew, Mordred. He started a civil war against Arthur, which climaxed in the bloody Battle of Camlann. His character is very intriguing since there is ostensibly some conflict between the way he is presented in Welsh tradition and the way he is presented in non-Welsh romances. In this article, we will examine what the sources claim about him and how his character evolved over the centuries.
The Earliest Traces of Mordred

The very earliest trace of this Arthurian character comes from the Annales Cambriae. This is a 10th-century Latin chronicle from Wales. It refers to only two Arthurian events. One is the Battle of Badon, Arthur’s greatest and final victory against the Saxons. The other is the Battle of Camlann. The text reads:
“The strife of Camlann, in which Arthur and Medraut fell; and there was plague in Britain and Ireland.”
As we can see from this, Arthur and Mordred, whose name here is spelled “Medraut,” are both linked to this battle. They are both described as “falling” at this battle, which is usually taken to mean that they died. It is frequently pointed out that the text does not actually say whether Arthur and Medraut were on the same side or on different sides. Nevertheless, we can discern that this must have been a civil war since the Annales Cambriae places it just 21 years after the Battle of Badon. Gildas, the 6th-century monk, explained that only civil wars had occurred during the 43 years since Badon.
Mordred in Geoffrey of Monmouth’s Account

After this, the next earliest description of Mordred comes from Geoffrey of Monmouth’s Historia Regum Britanniae, written in c. 1137. In this account, which is the earliest full account of Arthur’s career, Mordred’s name is written “Modredus.” He is described as Arthur’s nephew, the son of his sister Anna, and her husband, Lot of Lothian. He does not have a prominent role in the narrative until right at the end of Arthur’s career. During one particular expedition to Gaul, Arthur leaves his kingdom in the hands of Mordred.
However, after defeating the Romans during a battle on the continent, Arthur receives news that Mordred has rejected his position of regent and has actually declared himself king. Arthur rushes back to Britain and battles against Mordred’s forces. After several battles, the two armies make their final stand at a valley called Camlann. Here, Arthur manages to defeat Mordred’s army, but he himself suffers a mortal wound and the destruction of most of his own forces.
How Mordred’s Character Evolved

Geoffrey’s Historia Regum Britanniae was massively influential. Many Arthurian accounts that came after it followed its basic narrative, with Mordred emerging as Arthur’s final opponent. Mordred’s position as Arthur’s treacherous kinsman remained virtually unchanged throughout the medieval Arthurian legends. However, Mordred’s character did change in several important ways.
One of the biggest changes was introduced in the Vulgate Cycle. Within this corpus of Arthurian literature, there is a story in which Arthur himself fathers Mordred through accidentally committing incest with his sister. It has been suggested that this change was invented to make Mordred’s final betrayal appear more tragic.
A detail which emerged in the Post-Vulgate Cycle, and which was cemented in tradition by Thomas Malory, is that Arthur attempted to kill all the babies born around the time of Mordred’s birth. He did this because Merlin prophesied that a child born then would eventually cause his downfall. Mordred, however, was saved from this massacre and eventually grew up to do what Merlin had prophesied.
Mordred in Welsh Tradition

The Arthurian legends are Welsh stories at their core. As we saw earlier, Mordred’s first appearance is in the Annales Cambriae, which is a document from Wales. It is, therefore, not surprising that this figure appears in medieval Welsh tradition. He appears in Welsh translations of Geoffrey of Monmouth’s account, several triads from the Welsh Triads, and a number of medieval poems.
In the Welsh prose tale Culhwch and Olwen, from c. 1100, there is a reference to Arthur’s nephew Gwalchmai. He is equivalent to Sir Gawain, the brother of Mordred in non-Welsh texts. His mother is named Gwyar and is called Arthur’s sister. Hence, although Mordred himself is not mentioned in this text, it shows that Mordred’s supposed brother was indeed remembered as Arthur’s nephew by his sister.
It is somewhat later, in the Welsh translations of Geoffrey’s work, that Mordred explicitly appears as Arthur’s nephew as well. In these translations, such as Brut Tysilio, Mordred’s name is spelled “Medrawd.”

The Welsh translations frequently alter Geoffrey’s spellings or sometimes change names entirely to bring them more in line with standard Welsh tradition. For instance, Arthur’s sister, the mother of Gwalchmai, is called Gwyar, not Anna. Mordred’s father, Lot of Lothian, is called Llew ap Cynfarch. He is known from a variety of Welsh texts. The form “Lot” appears to come from an alternative shortening of “Lleuddun,” the full form of this figure’s name.
The Welsh Triads also speak of Medrawd in several places. One triad refers to the time when Medrawd ravaged Arthur’s royal court, leaving neither food nor drink there. It also explains that he dragged Arthur’s wife, Gwenhwyfar, from her throne and struck her. A variant version from a different triad mentions that Arthur struck Medrawd. Another triad, which displays strong influence from Geoffrey of Monmouth, recounts an overview of the same basic story told in the Historia Regum Britanniae.
Was Mordred Originally a Hero?

As we can see from the evidence above, Welsh tradition contains several references that show clear hostility between Arthur and Medrawd, or Mordred. This includes references that display no influence whatsoever from Geoffrey’s Historia Regum Britanniae. Therefore, an interesting enigma emerges when we also consider mentions of Medrawd that appear to be favorable.
One example of this is a triad that describes Medrawd in glowing terms as one of the Three Royal Knights of Arthur’s Court.
A Welsh poet writing in c. 1137 praised his patron as having Medrawd’s nature, apparently a reference to courage in battle. That poet’s son went on to compose a poem in which he referred to his patron as having Medrawd’s good nature. For these reasons, it has been argued that Mordred was originally viewed as a hero in Welsh tradition. According to this theory, it was only due to Geoffrey of Monmouth’s work that he became known as a traitor.

However, does this theory really stand up to scrutiny? Notably, all but one of the mentions of Mordred from Welsh tradition come from after Geoffrey of Monmouth wrote the Historia Regum Britanniae. The only one that may not is the reference from c. 1137. In any case, Geoffrey’s work was highly influential both inside and outside of Wales. Hence, the poets who made positive comparisons to Mordred did so, knowing that he had become well-known as a traitor. This is the case regardless of whether he was known as a traitor before Geoffrey wrote or not. Therefore, those poets evidently did not see anything wrong with positively comparing their patron to someone who was, at the time they were writing, known as a traitor.
The simple explanation is evidence that these positive comparisons and mentions were made about Mordred from before he became a traitor. After all, the fact that Arthur was portrayed as leaving Britain in Mordred’s care while he was away from Britain indicates that he was one of Arthur’s best knights.
This would be similar to how the Biblical gospels favorably compare Jesus to Solomon, even though Solomon famously became wicked at the end of his life.
What We Know About Mordred, Arthur’s Treacherous Nephew

In conclusion, we can see that Mordred is an important figure from the legends of King Arthur. He is one of the very earliest characters from the legends, being mentioned in the Annales Cambriae of the 10th century. He could well have been a historical figure. Although that early source does not reveal who he was, later records consistently make him Arthur’s kinsman. He is portrayed as Arthur’s nephew in the earliest records, while later versions make him Arthur’s son. In either case, the legends portray him as causing the downfall of Arthur’s kingdom by starting a civil war, which climaxed in the Battle of Camlann.
Welsh tradition, including in references that are clearly independent of Geoffrey of Monmouth, speaks of the hostility and conflict between Arthur and Mordred. We see this primarily in the Welsh Triads. While there are some positive references to Mordred in those triads, as well as in Welsh tradition, there is no solid basis for concluding that there was some alternative tradition in which he was never a traitor.









