Achtan inion Olc Acha

Achtan, fl. c. 1st-2nd centuries AD, mother of Cormac mac Airt.

Achtan and Art mac Cuinn In the Irish saga, Cath Maige Mucrama, Achtan is named as the daughter of Olc Acha of the Crich Óic Bethra, near what is now Clarenbridge, County Galway. The night before the Battle of Mag Mucrama, Art mac Cuinn he was a guest of Olc Acha, who asked him how many children he had. To ensure the survival of his bloodline in case of his death, Olc Acha proposed Art sleep with Achtan and conceive a son.

"It was then that Cormac was conceived. He (Art) told her she would bear a son and that that son would be king of Ireland. Then he told her of every hoard he had hidden for the benefit of that son. And he said that he would be killed the following day and he takes leave of her. He told her to bring her son for fostering to his friend among the Connachtmen. And on the following day he went to the battle."

Achtan gave birth to Cormac mac Airt, ancestor of the Connachta, making her ancestor of Irish dynasties such as Uí Fiachrach, Uí Briúin, Uí Ailello, Muintir Murchada. Families descended from these dynasties include MacDermot, O'Conor, Ó Cléirigh, O'Flaherty, O'Dowd, O'Shaughnessy, McGivergan and O Hynes.