Fainche (6th cent.), anchoress, abbess of Ros Airthir (Rossory, Co. Fermanagh), and saint in the Irish tradition, most likely belonged to the dynasty of Cenél Lóegaire. Later medieval genealogies (Book of Lecan and Leabhar Breac) name her father as Crimthann son of Guaire – a grandson of the eponymous Lóegaire (qv) – whose collateral descendants in the historical period ruled a petty kingdom around Trim, Co. Meath. In that event, she was a niece of Áed son of Guaire who established a church at Gabal Mucraite (Lisgoole, parish of Rossory) on the shore of Lough Erne. An alternative tradition (accepted by Colgan), related in the Latin Life of Énnae (qv) of Aran, makes her his sister and so a daughter of Conall Derg son of Daimín, an Uí Chremthainn king of Airgialla. By extension, she was therefore a sister of Cairech of Cluain Bairenn, and of Lóichéne and Daráine.
However, this alleged family relationship, and indeed the prominence of Fainche in the hagiography of Énnae, may reflect the absorption of her foundation (or foundations) into the latter's familia; it appears from some episodes in the Life that she did not belong to his nuclear family, but was a sister in religion only. It is claimed that Fainche, when she reached young womanhood, opted out of a marriage-agreement with the Éoganacht king of Cashel, Óengus (qv) son of Nad-fraích, by persuading her ‘sister’ Daráine to marry him instead. Subsequently she became an anchoress, and is represented as Énnae's inspiration and conscience. She is said to have reproached him for seeking to avenge his father's death, and secured his conversion to the religious life when a postulant whom he sought in marriage providentially died. In return, he founded Cell Áine (or Cell Fainche?, perhaps Killanny, Co. Louth) for her. Later she castigated him when he attempted to retaliate against raiders who attacked his church; she subsequently followed him to Rome, where she became the first to learn of his plans to establish a monastery on the Aran Islands.
Nevertheless, traditions relating to Fainche are also preserved in other sources. The story of her refusal of an arranged marriage (a common motif in the hagiography of religious women) also features in the late twelfth-century notes to the Martyrology of Óengus (qv) (fl. c.830). According to this account, she fled to the saintly Diarmait (qv) son of Lugna at Inis Clothrann to seek his advice. It seems that her principal foundation was Ros Airthir which, significantly, was quite near the foundation of Áed son of Guaire. In time she was joined by other women and so became head of a community. She is also associated with other sites, including Cluain Chaín (in the kingdom of Éoganacht Chaisil), Tech Fainche, and Cell Fainche (both unlocated). It is not clear whether these represent personal foundations or cult dissemination; the tract on homonymous saints lists several holy women named Fainche, with some apparent cases of duplication, which seems to suggest cult-fragmentation.
The year of her death is not recorded, but might reasonably be placed in the first half of the sixth century. She probably died on 21 January, under which date is commemorated Fainche of Cluain Chaín, who appears to be the same individual (Mart. Tall., cf notes to Mart. Óeng.). According to the Life of Énnae, she died on the return journey from Rome and her body was brought to Cell Áine. Her foundation of Ros Airthir survived (or was reestablished) as a community of women religious till the eleventh century or later; a church was erected there in 1084 (AFM).