Historicity of King Arthur

The historicity of King Arthur has been debated both by academics and popular writers. While there have been many claims that King Arthur was a real historical person, the current consensus among specialists on the period holds him to be a mythological or folkloric figure.

The first definite mention of Arthur appears circa 828 in the Historia Brittonum, where he is presented as a military leader fighting against the invading Saxons in 5th- to 6th-century Sub-Roman Britain at the Battle of Badon, written more than three centuries after the events depicted. He develops into a legendary figure in the Matter of Britain from the 12th century, following Geoffrey of Monmouth's influential but largely fictional Historia Regum Britanniae.

Historians propose a variety of possible sources for the myth of Arthur, perhaps as a composite character. Historical figures involved in such theories include Artuir mac Áedán, a son of the 6th-century king of Dál Riata in modern Scotland; Ambrosius Aurelianus, who led a Romano-British resistance against the Saxons; Lucius Artorius Castus, a 2nd-century Roman commander of Sarmatian cavalry; and the British king Riothamus, who fought alongside the last Gallo-Roman commanders against the Visigoths in an expedition to Gaul in the 5th century. Others include the Welsh kings Owain Danwyn, Enniaun Girt, and Athrwys ap Meurig.