Munnu of Taghmon

Munnu of Taghmon, called Fintán in Ireland, died in 635. He was founder and abbot of the monastery of Teach-⁠Mhunn ("House of Munn"), today Taghmon in County Wexford. He is venerated as a saint in the Western Church, and in Scotland he is regarded as patron of Clan Campbell.

He was born of the dynasty of Niall; according to the Félire of Oengus his father was a druid. He may have studied at Bangor under Saint Comgall, but it is more certain that he studied eighteen years under Abbot Sinell at Cluain-⁠inis in Lough Erne. In 579 he crossed to Scotland. In 597 he resolved to go to Saint Columba's monastery on Iona, but just before leaving he learned that Columba had reposed and that Baíthéne had succeeded him. Baíthéne would not receive him as a monk, saying that Columba had foretold that Fintán would be an abbot and a guide of souls and must return to Ireland to found a monastery in Leinster. In Scotland he lived on Loch Leven and founded a community at Kilmun.

Back in Ireland, he received land around 597 from a lord of Wexford, Dímma, and built the monastery of Teach-⁠munnu, a centre of learning, where he presided over one hundred and fifty-⁠two monks. He was versed in the sciences and gave public lectures. The sources also speak of him as a leper.

Toward the end of his life he opposed, with Laserian, the adoption of the Roman reckoning of Easter. The synod at Magh Lene (631) did not settle the matter, and a delegation was sent to Rome. Munnu withdrew his opposition and adopted the Roman system with the rest of southern Ireland. His feast is 21 October, according to the Western calendar (new style).