The King Arthur of Arthurian legend is largely a product of Sir Thomas Mallory's 1485 compendium Le Morte d'Arthur, which collected and edited a variety of earlier French chansons de geste, the Arthurian legends written by Geoffrey of Monmouth in the tweflth century, and some original material. This forms the basis of most of the popular Arthurian myth.

Geoffrey of Monmouth's Arthurian legends appear in his Historia Regum Britanniae which is often quite... liberal with its application of the truth, although did see a resurgence in popularity in the centuries after it first appeared. At the time of its first writing, Geoffrey's Historia is lambasted by Gerald of Wales for being utter nonsense, which coming from Gerald of Wales of all people is quite damning.

Despite Geoffrey's history, no 'Arthur' appears in Gildas' De Excidio et Conquestu Britanniae, his polemic on the fall of Britain to the Anglo-Saxons, even though Gildas does mention the Battle of Badon which Arthur supposedly won. Arthur is similarly absent from the Anglo-Saxon Chronicle or Bede's Historia ecclesiastica even though these do mention Romano-British leaders like Vortigern. An Arthur is mentioned in the Welsh Historia Brittonum and copied from that into the Annales Cambriae but there are significant doubts over its veracity.

There have been various attempts to find archaeology of Alfred. A 6th century female grave exhumed at Glastonbury was widely purported to be the grave of Guinevere, completely overlooking that plenty of noblewomen both lived and died throughout the 6th century and necessitated burial. Recent excavations at Tingtagel have potentially located a late Iron Age hall complex, but to call this 'Camelot' is very wilful.

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