Fintan is known in Goidelic mythology as the Wise. He was born before the deluge. His full name is Fintán Mac Bóchra.

His mother was Bochra. He had 16 wives due to the fact that he and two other men (Cessair's father Bith, and the pilot Ladra) were shipwrecked on the coast of Ireland with fifty women, having to share the women between them. His wives are named: Cessair, Lot, Luam, Mall, Mar, Froechar, Femar, Faible, Foroll, Cipir, Torrian, Tamall, Tam, Abba, Alla, Baichne, and Sille. He married Ebliu later.

His only son was Illann.

Fintan was the first to land on Ireland before the deluge. His wives and children are drowned when the flood arrives but he survives in the form of a salmon, remaining a year under the waters in a cave called "Fintán's Grave." He then turns into an eagle and then a hawk then turns back to human form. He lives for 5500 years after the Deluge, becoming an advisor to the kings of Ireland, known as Fintan the Wise.

In this capacity he gives advice to the Fir Bolg king Eochaid mac Eirc when the Tuatha Dé Danann invade. He even joins in the fight at the First battle of Moytura. He survives into the time of Cúchulainn, Fionn and Oisín. He is the repository of all knowledge of Ireland and all history along with a magical hawk who was born at the same time as him. They meet at the end of their lives and recount their stories to each other. They decide to leave the mortal realm together sometime in the fifth century (after the invasion of the Christians to Ireland).

See: Fintan's Grave, Tul Tuinde.

Note: As far as known he is not any relation to Father Fintan Stack from Father Ted.