Fergal mac Máele Dúin

Fergal mac Máele Dúin (died 11 December 722) was High King of Ireland. Fergal belonged to the Cenél nEógain sept of the northern Uí Néill. He was the son of Máel Dúin mac Máele Fithrich (died 681), a King of Ailech, and great grandson of the high king Áed Uaridnach (died 612). He belonged to the Cenél maic Ercae branch of the Cenél nEógain and was King of Ailech from 700 to 722.

As King of Ailech Fergal participated in a victory over the men of Connacht in 707 where their king Indrechtach mac Dúnchado was slain. This was in revenge for the defeat and death of the high king Loingsech mac Óengusso in 703 at the Battle of Corann. Loingsech's son Fergal mac Loingsig was one of the participants.

Fergal became High King in 710, on the death of Congal Cendmagair of the Cenél Conaill. He ruled from 710 to 722.

The Cenél nEógain were expanding eastwards into Airgialla territory. In 711 he fought the Battle of Sliab Fuait (in the Fews, modern County Armagh) where the king of Uí Méith, Tnúthach son of Mochloinges, and Cú Raí mac Áedo of the Fir Cúl sept of the Síl nÁedo Sláine of Brega were slain. Hostility to the Síl nÁedo Sláine was evidenced by the expulsion of Fogartach mac Néill (died 724) from the kingship of Brega in 714 who went into exile in Britain. This appears to be the work of Fergalin in conjunction with Murchad Midi (died 715) the King of Uisnech of Clann Cholmáin and Murchad may have been Fergal's deputy ruler in the south.

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