Cynlas Goch, King of Rhos
Owain Danwyn (White-Tooth)'s eldest son, "Cuneglasus" alias Cynlas the Red, is mentioned by the early 6th century St. Gildas as one of his contemporary tyrannical usurpers. The saint gives us something of the man's background, revealing that he ruled his Kingdom from Din-Arth, a hillfort above Llandrillo-yn-Rhos: "You Bear, rider of many and driver of the Chariot of Dineirth".
This statement has led to enthusiastic attempts to connect both Cynlas and his father with King Arthur. Cynlas was accused of inciting Civil War, probably in an attempt to throw off the shackles of King Maelgwn Gwynedd's overlordship. He was also condemned for the abandonment of his wife and marriage to his erstwhile sister-in-law whom he had dragged from her nunnery! Strangely, he is recorded as a patron of the church and joint-founder of Penmon Priory on Ynys Mon (Anglesey).