Cenn Fáelad mac Aillila

Cenn Fáelad mac Ailella (alias Cennfaeladh) (died 679) was an Irish scholar renowned for having his memory markedly improve and possibly becoming eidetic after suffering a head wound in battle.

He was a member of the Cenél nEógain, being a grandson of King Báetán mac Muirchertaig (King of Cenél nEógain), a great-great-great-great grandson of Niall Noígiallach, and a first cousin once removed of Aldfrith of Northumbria via his first cousin, Fina.

His father Ailill mac Báetán was murdered in Templeport, County Cavan according to the Annals of Ulster- "U620.1. The slaying in Magh Slécht in the territory of Connacht of the kindred of Báetán, i.e. of Ailill son of Báetán and of Mael Dúin son of Fergus son of Báetán; and the death of Fiachra son of Ciarán son of Ainmire son of Sétna." According to John Healy, Cenn Fáelad's sister Sabina was the mother of Saint Cuthbert of Lindisfarne.

Cenn Fáelad fought at the crucial Battle of Moira or Magh Rath (Moira, County Down) in 636. During the battle he received a life-threatening head wound, and was afterwards carried to the abbey of Tomregan, County Cavan to be healed in the house of its abbot, Saint Bricín. That this abbey was situated beside Magh Slécht where his father had been slain 16 years earlier may not be a coincidence. His family possibly had land there. This house was situated "where the three streets meet between the houses of the three professors. And there were three schools in the place; a school of Latin learning, a school of Irish law and a school of Irish poetry. And everything that he would hear of the recitations of the three schools every day he would have by heart every night."

Tradition states that as a result of a head wound, Cenn Fáelad's "brain of forgetting was knocked out of him." The effect of this trauma led him to create "a pattern of poetry to these matters and he wrote them on slates and tablets and set them in a vellum book."

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