Oxford Dictionary of National Biography

Nennius [Ninnius, Nemniuus] (fl. c. 770–c. 810), scholar, is commonly, but most certainly incorrectly, regarded as the author of the early ninth-century Cambro-Latin historical compilation Historia Brittonum. The ascription to Nennius occurs in just one of the numerous recensions of the text, the so-called ‘Nennian recension’, which survives in five medieval manuscripts. The earliest and primary recension (the Harleian) offers no identity for the author, while most others attribute the text, equally erroneously, to Gildas. No original copy of the Nennian recension survives, but between 1164 and 1166, at the Cistercian abbey of Sawley, Yorkshire, three different scribes collated the same (now lost) copy of the recension with the Gildasian recension which is now in Corpus Christi College, Cambridge, manuscript 139. The Nennian material was accordingly added to this manuscript as a series of interlinear and marginal annotations plus the prologue and this composite text is the archetype of all other copies of this recension. The Nennian recension seems to have been created in north Wales (possibly Anglesey) in the first half of the eleventh century, probably by a scribe called Euben (Owain) under the direction of his clerical magister, Beulan; and it was probably at this stage that the prologue attributing the Historia to Nennius was composed. This prologue describes him as (Ninnius Eluodugi discipulus (‘Ninnius disciple of Elfoddw’)). If Elfoddw is the bishop of Bangor of that name who in 768 was responsible for bringing the Welsh church into conformity in the Paschal question and who died in 809, and assuming the connection with Ninnius is reliable, then Nennius would have lived at some time between about 770 and 810. Furthermore, Nennius may be identified with the Nemniuus said to have composed an alphabet based on Old English runic ‘futhorc’, but adapted to Old Welsh orthography, which is preserved in a manscript written in 817. This would suggest that the historical Nennius was a Welsh scholar with linguistic interests and specifically with a familiarity with things English, perhaps explaining in part why the creators of the Nennian recension believed him to have been the author of the Historia.