Óengus mac Nad Froích

Óengus mac Nad Froích (430-489) was an Eoganachta and the first Christian king of Munster. He was the son of Nad Froich mac Cuirc by Faochan, a British lady (called daughter of the King of Britain). In Geoffrey Keating's History of Ireland Oengus is given a reign of 36 years which would place the start of his reign as early as 453.

He was baptized a Christian in the royal seat of Cashel by Saint Patrick himself and imposed a baptismal tax on the Christian converts of Munster for St. Patrick. It is mentioned that half of his numerous progeny were given into the church. St Patrick baptized him in blood by driving his crozier through the king's foot. The king became very devout and surrounded himself with clerics.

In 489 was fought the battle of Cenn Losnada in Mag Fea in which he was slain. His wife Eithni Uathach ingen Cremthainn, called "the hateful", was also killed. She was a member of the Uí Cheinnselaig sept of the Laigin. The victors included Iollann mac Dunlaing, and Oilill, his brother of the Uí Dúnlainge sept of Laigin, and Eochaidh Guinech of the Uí Bairrche sept of Laigin, and Muirchertach Mac Ercae, the Ui Neill king of Ailech. His head was given to Iollan.

Óengus appears in the 9th-century literary text The Expulsion of the Déisi, in which he grants land to the wandering Déisi horde. The story is set in the time of Cormac mac Airt, who is said to have lived 200 years before Óengus. He also appears often in the varying vitae of St. Ciarán of Saigir as a major patron of the saint.

He was the ancestor of three major septs of the Eoganacht including the Cashel, Arithir Cliach, and Glendamnach lines.

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