Cador (Latin: Cadorius) is a legendary Duke of Cornwall, known chiefly through Geoffrey of Monmouth's pseudohistorical Historia Regum Britanniae and previous manuscript sources such as the Life of Carantoc.
[note 1] Many stories involving Arthurian figures were told orally, leading to many interpretations and versions of the people, events, and characters.
[3] Scholars question the historical accuracy of these tales and most have been discredited, so the people associated with him could conceivably have been added by later storytellers.
Cador Duke of Cornwall was summoned to Arthur's court and may have been a real historical figure, but the diversity of interpretations and stories that include him make it difficult to understand his true context.
[citation needed] Traditionally, he was Arthur's good friend and even shared his throne in the Vita Sanctus Carantoci (Life of St. Carantoc).
[9] Cador, mainly mentioned by Geoffrey of Monmouth, has also been called by two other names, Cado and Cadwy, in the Myvyrian and Life of S. Carannog and in early fifteenth century pedigrees.
Since it names only one British commander, Vortigern, scholars have aligned the timelines in the Anglo-Saxon Chronicle and the Historia Regum Britanniae to assess the legitimacy of Cador.
The unnamed British commander in the Anglo-Saxon Chronicle has been posited to be the Cador of Historia Regum Britanniae because of their similarities.
He won both battles, easily defeating the army in York and also killing Chelric, the leader of the Saxons, on the Isle of Thanet.
[12] In addition to his brothers, he had a sister named Gurguint who married Caradoc Vreichfas, a legend of Welsh prehistory who lived at same time period as Arthur.
In the Brut Tysilio, the translator adds that Cador was the son of Gorlois, presumably by Igraine, which would make him Arthur's maternal half-brother.
This story appears in Richard Hardyng's Chronicle which refers to Cador as Arthur's brother "of his mother's syde."