Niall Caille

Niall mac Áeda (died 846), called Niall Caille (Niall of the Callan) to distinguish him from his grandson Niall mac Áeda (died 917), was High King of Ireland.

Niall belonged to Cenél nEógain, a northern branch of the Uí Néill, a kin group whose rulers dominated large parts of Ireland. He was the son of Áed mac Néill (died 819), called Áed Oirdnide, who had himself been High King. According to the 12th century Banshenchas (Lore of Women), his mother was Medb, daughter of Indrechtach mac Muiredaig of the Uí Briúin of Connacht.

The High Kingship of Ireland was in practice shared between Cenél nEógain of the north and the southern Clann Cholmáin branch of the Uí Néill, so that when Niall's father died, he was not succeeded by his son, or by a cousin, but by Conchobar mac Donnchada of Clann Cholmáin, whose father Donnchad Midi had been High King before Áed. Nor did Niall immediately succeed to the leadership of Cenél nEógain on his father's death. His second cousin Murchad mac Máele Dúin was chosen to be King of Ailech and chief of Cenél nEógain. It was not until 823, when the Annals of Ulster record that Murchad was deposed, that Niall became king of Ailech.

In 827 a conflict within the important church at Armagh led to war. The late Annals of the Four Masters provide a long account of the events. According to this, Cummascach mac Cathail of the Uí Cremthainn, king of the Airgíalla, expelled Niall's confessor Éogan Mainistrech from Armagh, installing his own half-brother, Artrí mac Conchobair, who may have been the son of High King Conchobar mac Donnchada, as abbot of Armagh. The Annals of Ulster describe Artrí as bishop of Armagh in 825 when he imposed the Law of Patrick on Connacht together with Feidlimid mac Crimthainn, the King of Munster, suggesting that he was both acting abbot and as such the spiritual heir of Saint Patrick.

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