Mathgamain mac Cennétig

Mathgamain mac Cennétig (contemporary name - Mahon, son of Kennedy) was King of Munster from around 970 to his death in 976. He is the elder brother of Brian Bóruma and the ancestor of the McMahon family of County Clare in Western Ireland (Thomond).

Mathgamain was the son of Cennétig mac Lorcáin of the Dál gCais. His father died in 951 and is called king of Tuadmumu in the report of his death, and was probably succeeded by Mathgamain's brother Lachtna, who died in 953 and is not given any distinguishing title at his death.

In 967, Mathgamain is called "king of Cashel", by the Annals of Ulster. However he is not believed to have become king of Munster until 970 or shortly after, after deposing Máel Muad mac Brain.

In 967 Mathgamain defeated Ivar of Limerick in the celebrated Battle of Sulcoit, following raids by Mathgamain into Ui Fidgente territory in 964.

The most common account as to Mathgamain death was that he was captured in 976 by Donovan (Donnubán mac Cathail), Tiarna (sept chief) of Uí Fidgenti, with whom the Dál gCais were rivaling for territory, and who were then in alliance with Ivar of Limerick. Donnubán handed him over to his most powerful ally Máel Muad mac Brain (Malloy, son of Brain) previous king of Munster, who had Mathgamain killed.

"Dalcassian historians say that Donobhan invited Mahon to a banquet in his house at Bruree and there, in violation of the laws of hospitality, seized and delivered him to the agents of his rival, Mulloy, who took him into the country of Cork and put him to death. Others of them say, that the Eoghanacht and Daleassian armies, after several battles, were face to face near Bruree, when the Bishop of Cork and the clergy interfered and proposed a conference at the house of Donobhan, who there betrayed Mahon to his enemy, receiving lands in Corea Laidhe as a reward.

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