King Arthur is an important figure in the mythology of Great Britain.
He is the central character in Arthurian legends (known as the Matter of Britain), although there is disagreement about whether Arthur, or a model for him, ever actually existed and in the earliest mentions and Welsh texts he is never given the title "king".
Early texts refer to him as dux bellorum ("war leader") and High Medieval Welsh texts often call him amerauder ("emperor").
However, a recent translation of newly discovered documents may have referred to him as a king.
One school of thought believes Arthur to have lived some time in the late 5th century to early 6th century, to have been of Romano-British origin, and to have fought against the Saxons.
His power base was probably in either Wales, Cornwall or the west of what would become England, but controversy over the centre of his power and the extent and kind of power he wielded continues to rage.
Some members of this school, most notably Geoffrey Ashe and Fleuriot, have argued for identifying Arthur with one Riothamus, "King of the Brettones", who was active during the reign of the Roman Emperor Anthemius.
Unfortunately, Riothamus is a shadowy figure of whom we know little, and scholars are not certain whether the "Brettones" he led were Britons or Bretons.
Other members suggest that Arthur should be identified as one Lucius Artorius Castus, a historical Roman of the 2nd century, whose military exploits in Britain may have been remembered for years afterward. 535–600) writes of one of his subjects that "he fed black ravens on the ramparts, although he was not Arthur" — but this poem as it currently exists is full of interpolations, and it is not possible to decide if this passage is an interpolation from a later period.
Another school of thought believes that Arthur is at best a half-forgotten Celtic deity devolved into a personage (citing sometimes a supposed change of the sea-god Lir into King Lear) or a possibly fictive person like Beowulf. Possibly of an earlier date are the following poems attributed to Taliesin: The Chair of the Sovereign — which refers to "Arthur the Blessed" — Preiddeu Annwn ("The Treasures of Heaven") which mentions "the valour of Arthur" and states "we went with Arthur in his splendid labours", and the poem "Journey to Deganwy" which contains the passage "as at the battle of Badon with Arthur, chief giver of feasts, with his tall blades red from the battle which all men remember".
Subscribers to this school of thought argue that another Roman Briton of this period, for example Ambrosius Aurelianus, led the forces battling the Saxons at the battle of Mons Badonicus. Another early reference to Arthur is in the Historia Britonum, attributed to the Welsh monk Nennius, who is said to have written this compilation of early Welsh history around the year AD 830.
In this work Arthur is referred to as a "leader of battles" rather than as a king.