Aneirin

Aneirin or Neirin was a late 6th century Brythonic poet. He is believed to have been a bard or 'court poet' in one of the Cumbric kingdoms of the Old North or Hen Ogledd, probably that of Gododdin at Edinburgh, in modern Scotland. From the 17th century, his name was often incorrectly spelled Aneurin.
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[Arthurian] Northern British bard, mentioned in the Historia Brittonum (one of several). Most likely lived in the sixth- early seventh century. His most renowned work is the Gododdin, a string of laments for the nobles killed at the battle of Catraeth, the culmination of a doomed expedition against the Angles around 600. He claimed to have been with the troops and was spared only because of his fine songs. Though elaborated over time and by scribal addition, the authentic passages are some of the most valuable specimens of Old Welsh poetry that illustrates the style of composition in which Arthurian legend began to take form. The work contains an allusion to Arthur, that if not the result of embellishment, is the earliest know mention of him by name.