Mac Cairthinn of Clogher

Saint Mac Cairthinn, also Macartan, McCartan (died 506), is recognized as the first presiding Bishop of Clogher from 454 to his death. One of the earliest Christian saints in Ireland, he is known as Saint Patrick's "Threin Fhir", or "Strong Man" for his dedication and faithfulness to the fledgling Church. His feast day is 24 March.

Legend Saint Macartan grew up in the southern part of Ireland, somewhere in Munster. Before his conversion to Christianity by Patrick, the future saint was known by the name Aidus/Aedh, the son of Caerthen (son of the Rowan Tree). The identity of his father is uncertain but is sometimes associated with a Dalcassian prince of Thomond or with the Uí Maine of Connacht. Hence the Anglicized later name to come down to us is "Macartan". Some sources claim that he was uncle to Saint Brigid. Macartan was initially ordained to the role of presbyter.

He was the "staff of Patrick" in the Irish patron saint's declining years. On one occasion after carrying Patrick over a river, an exhausted Macartan expressed a wish that he might be relieved from further travel and allowed to settle down in charge of some church close by his beloved master where he could spend the evening of his life in peace. Patrick, full of sympathy for his faithful companion and friend, agreed that he should establish a monastery in Clogher, and finish out his life there. A monastery was established near the ancient royal fort of Rathmore on the outskirts of the town and one of Ireland's oldest bishoprics was established. To commemorate the occasion Patrick gave Macartan his staff and a number of precious relics contained in a shrine known to tradition as the Domnach Airgid. On the cover of the Domnach Airgid is one of the earliest surviving metalwork images of St. Patrick. Traditionally, the book was claimed to be that given by St Patrick himself to his companion St Macartan, making it an object of great veneration. Around 1350, the abbot of Clones, John O Carbry, commissioned a substantial remodelling of the Domnach Airgid.