The Shapeshifter King
Mongán mac Fiachna was a historical king of Dal Fiatach in Ulster in the early seventh century who accumulated more supernatural stories around him than almost any other figure who can be historically confirmed. He died around 625 AD. The stories about him treat his supernatural nature as an open fact.
His divine father was Manannán mac Lir. The conception was a transaction. Fiachna Finn — Mongán’s mortal father — was fighting in Scotland and losing badly. Manannán appeared to Fiachna’s wife and offered a deal: he would go to Scotland in Fiachna’s form, fight beside him, and turn the battle, if she would lie with him that night. She agreed, to save her husband. Manannán kept his word. When Fiachna returned, Manannán told him the truth. Fiachna raised Mongán as his son. The divine parentage was not hidden — it explained everything exceptional about the boy.
Mongán was a shapeshifter. He could take any form — man, woman, animal. He was also said to be the reincarnation of Fionn mac Cumhaill. He made that claim himself in a dispute with a poet who had described Fionn’s death inaccurately. Mongán said the poet was wrong. He knew how Fionn had actually died because he had been Fionn. He proved it through Otherworldly knowledge, producing a witness and a weapon from three centuries before. The dispute ended in his favour.
His death was prophesied — a stone from a sling, thrown by an adversary. The shapeshifter who could become anything was killed by a stone, in the most ordinary way a man can die.
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