Mo Chutu of Lismore

Who was Mo Chutu of Lismore?

Saint Mo Chutu mac Fínaill, also known as Carthach or Carthach the Younger, was abbot of Rahan, Co. Offaly, and subsequently, founder and first abbot of Lismore, Co. Waterford. The saint's Life has come down in several Irish and Latin recensions, which appear to derive from a Latin original written in the 11th or 12th century.

Through his father Fínall Fíngein, Mo Chutu belonged to the Ciarraige Luachra, while his mother, Finmed, was of the Corco Duibne. Notes added to the Félire Óengusso claim that his fosterfather was Carthach mac Fianáin, that is Carthach the Elder, whose period of activity can be assigned to the late 6th century.

Mo Chutu first became abbot of Rahan, a monastery which lay in the territory of the southern Uí Néill. He composed a rule for his monks, an Irish metrical poem of 580 lines, divided into nine separate sections, a notable literary relic of the early Irish Church.

According to the Annals of Ulster, he was expelled from the monastery during the Easter season of 637. The incident has been connected with the Easter controversy, in which Irish churches were involved during the 7th century. Through his training in Munster, Mo Chutu may have been a supporter of the Roman system of calculation, which would have brought him into conflict with adherents of the 'Celtic' reckoning in Leinster.