Historia Brittonum

The History of the Britons (Latin: Historia Brittonum) is a purported history of the indigenous British (Brittonic) people that was written around 828 and survives in numerous recensions that date from after the 11th century.

The Historia Brittonum is commonly attributed to Nennius, as some recensions have a preface written in his name. Some experts have dismissed the Nennian preface as a late forgery, arguing that the work was actually an anonymous compilation.

The Historia Brittonum describes the supposed settlement of Britain by Trojan expatriates and states that Britain took its name after Brutus, a descendant of Aeneas. The work was the "single most important source used by Geoffrey of Monmouth in creating his Historia Regum Britanniae" and via the enormous popularity of the latter work, this version of the earlier history of Britain, including the Trojan origin tradition, would be incorporated into subsequent chronicles for the long-running history of the land, for example the Middle English Brut of England, also known as The Chronicles of England.

The work was the first source to portray King Arthur, who is described as a dux bellorum ('military leader') or miles ('warrior, soldier') and not as a king. It names the twelve battles that Arthur fought, but unlike the Annales Cambriae, none are assigned actual dates.

The reference in the Historia Brittonum of Arthur carrying the image of St. Mary on his shoulders during a battle has been interpreted by later commentators as a mistake for Arthur bearing the image of Mary on his shield, the error being caused by the similarity between the words in Welsh.

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