Mo Chutu mac Fínaill (died 14 May 639),[1] also known as Mochuda, Carthach or Carthach the Younger (a name Latinized as Carthagus and Anglicized as Carthage /ˈkɑːrθədʒ/),[2][3] was abbot of Rahan, County Offaly, and subsequently, founder and first abbot of Lismore (Irish: Les Mór Mo Chutu), County Waterford.

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.

[4] Following his expulsion, Mo Chutu journeyed to the Déisi, where he founded the great monastery of Lismore (in modern County Waterford).

The Latin and Irish Lives make very little of Mo Chutu's earlier misfortune and focus instead on the saint's resistance to the oppressive Uí Néill rulers and his joyous reception among the Déisi.

It was able to withstand the Viking depredations which plagued the area and benefited from the generosity of Munster kings, notably the Mac Carthaig of Desmond.