Fionn mac Cumhaill (Fionn mac Cumhaill)

Leader of the Fianna, who got his wisdom by accident and burned his thumb doing it.

He was born Demne, son of Cumhall, who had been killed leading the Fianna. His mother gave him to two women to rear in secret in the forests of Sliabh Bladhma, because the men who killed his father would kill him too. The name Fionn, fair or bright, came later.

His wisdom was an accident. He was apprenticed to the poet Finnéigeas on the Boyne, who had spent seven years trying to catch the Salmon of Knowledge, a fish that had eaten the hazelnuts falling into the well of Segais and so held all the knowledge in the world. Finnéigeas caught it at last and set the boy to cook it with strict instructions to eat none of it. Fionn burned his thumb on the hot skin, put it in his mouth, and the knowledge went to him instead. For the rest of his life he had only to put that thumb between his teeth to know whatever he needed.

As leader of the Fianna he is less a warrior than a presence: a hunter, a judge of men, and the fixed point the stories move around. He is also, in the Diarmuid and Gráinne material, old, slighted and vindictive, and the tradition does not protect him from that.

He does not get a death in the ordinary way. One strand of the tradition says he sleeps in a cave with the Fianna around him and will wake when Ireland needs him, which is a thing said about several heroes in several countries and never said about anyone whose grave is known.