Maelgwyn Hir (the tall)
also known as Maelgwyn Fawr or Maelgwyn Gwynedd
The first historically verifiable ruler of the kingdom of Gwynedd. Born sometime around 497 AD, he is believed to have reigned from about 530 to 547 AD.
The Welsh Genealogies record that he was the son of Cadwallon Lawhir (Longhand) and the great grandson of Cunedda, traditional founder of the kingdom of Gwynedd.
His existence is attested to by Gildas, who in his De Excidio Britanniae refers to him under the name Maglocunus, as the "dragon of the
island" and the "first in evil". Gildas records that in his youth Maelgwyn killed his uncle (presumably as part of a dynastic struggle), who later repented and turned to the Christian church, founded the bishopric of Bangor, built further churches before once again taking up a life of tyranny.
By which Gildas means that Maelgwyn reverted to the normal practice of seeking to dominate neighbouring kingdoms, killing his enemies and generally speaking, not behaving in the way that Gildas approved of.
Depsite Gildas's comdemnation, Maelgwyn was clearly one of the most powerful rulers of early sixth century Britain. The exact extent of the territory under his control is uncertain, other than that his capital was reputedly at Degannwy and that it was centred on Gwynedd.
The Annales Cambriae record his death from plague in 549 AD. He was succeeded by his son Rhun whilst another of his sons Bruide, supposedly became King of the Picts.