Nennius

Nennius — or Nemnius or Nemnivus — was a Welsh monk of the 9th century. He has traditionally been attributed with the authorship of the Historia Brittonum, based on the prologue affixed to that work, This attribution is widely considered a secondary (10th century) tradition.

Nennius was a student of Elvodugus, commonly identified with the bishop Elfodd who convinced British ecclesiastics to accept the Continental dating for Easter, and who died in 809 according to the Annales Cambriae.

Nennius is believed to have lived in the area made up by present-day Brecknockshire and Radnorshire counties in Powys, Wales. Thus, he lived outside the Anglo-Saxon kingdoms, isolated by mountains in a rural society. Because of the lack of evidence concerning the life of Nennius he has become the subject of legend himself. Welsh traditions include Nennius with Elbodug and others said to have escaped the massacre of Welsh monks by Ethelfrid in 613, fleeing to the north.

Nennius was traditionally credited with having written the Historia Brittonum c. 830. The Historia Brittonum was highly influential, becoming a major contributor to the Arthurian legend. It also includes the legendary origins of the Picts, Scots, St. Germanus and Vortigern, and documents events associated with the Anglo-Saxon invasion of the 7th century as contributed by a Northumbrian document.

Evidence suggests that this medieval literature was a compilation of several sources, some of which are named by Nennius while others are not. Some experts say that this was not the first compiled history of the Britons and that it was largely based on Gildas' De Excidio et Conquestu Britanniae written some two centuries before. Scholarship indicates that other sources included a Life of St Germanaius and a number of royal pedigrees. Most other sources have not survived and therefore cannot be confirmed. The surviving manuscripts of the Historia Brittonum appear to be redacted from several lost versions: information about Nennius contained in the Prologue and in the Apology differs, the Prologue containing an expanded form of the Apology that is only found in editions copied during the 12th century, leading experts to believe that later versions of the document were altered. The largest known edition contains seventy-six sections including the Prologue and the Apology. The work was translated into Irish by Giolla Coemgin in c. 1071 and is the earliest example of the original Historia Brittonum, but includes the author’s name, Nennius.

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