Three Prostrate Chieftains of the Island of Britain:
(And this is why those were called "Prostrate Chieftains": because they would not seek a dominion, which nobody could deny to them.)
"The original sense of the Triad was probably 'subdued by misfortune.' The later White Book explanation interprets lledyf
in the sense of a person who does not resist when others forcibly deprive him of his rights." --Jeff Davies
Llywarch Hen is attributed many poems in both the Red Book of Hergest and the Black Book of Carmarthen. Manawyddan ap Llyr is the same as that of the Mabinogion; this triad refers to the time that Caswallawn ap Beli stole the throne of Prydein from Manawyddan, as retold in the Third Branch of the Mabinogi. The final person, Gwgon, I'm not familiar with, though Peredur is the subject of his own story in the Mabinogion, wherein he is the equivalent of Perceval.
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