Comgall (d. 602), founder and first abbot of the monastery of Bennchor (Bangor, Co. Down), was born into the tribal territory of Dál nAraide in north-east Ulster in the early sixth century (506 Ann. Inisf.; 515 AU; his genealogy is given in LL, 348d33). One of his Latin Lives states that he received his first monastic training from a cleric ‘who had a house in the country’ and was of doubtful morals, keeping a female companion – probably an example of the tradition of uirgines subintroductae or syneisactism, known to have been practiced in the early Celtic church. According to tradition, he also received some of his early monastic training from Fintan (qv) (d. 603) of Clonenagh. He was afterwards ordained priest and established a small monastic community of extreme severity on an island in Lough Erne.
About 558 Comgall established the monastery of Bangor on the shores of Loch Laíg (Belfast Lough), which was to become one of the premier monastic foundations of early Ireland, numbering with its daughter houses a reputed 3,000 monks in the seventh century. Columbanus (qv) was trained there, and Jonas (qv) in his ‘Vita Columbani’ (i.4) refers to the severity of Comgall's Rule. The connections of Iona with Bangor are mentioned in the Latin Life of Comgall – dating to c.800 – and in Adomnán's ‘Vita Columbae’. The former relates that Colum Cille (qv), together with Cainnech (qv) and Comgall, visited Bruide, king of the Picts, at Inverness, probably with the object of seeking permission for the establishment of monasteries and the free movement of Irish missionaries in his kingdom. Adomnán (qv) relates only that Colum Cille with two unnamed companions visited Bruide. Comgall was also present at a ‘mass of the saints’ on Iona. There is no doubt therefore that ecclesiastical and missionary collaboration existed between the two foundations, and possibly also with the church of Cóemgen (qv) at Glendalough, which the ‘Vita S. Coemgeni’ (§27) attests. Jocelin of Furness, in his ‘Vita S. Patricii’ (§98), gives a short account of Comgall and Bangor, which is drawn from a Life possibly earlier than any now existing.
The monastery of Bangor was destroyed by viking raids (822, 823), and the relics of Comgall along with it. The only surviving remnant of Bangor's monastic culture is the small codex known as the Antiphonary of Bangor, which contains a collection of hymns, canticles, and other liturgical pieces dating to the end of the seventh century. Comgall is mentioned in the hymn ‘In memoriam abbatum nostrorum’, celebrating each of the abbots of Bangor from Comgall to Crónán (680–91), and in an alphabetical hymn in his honour (f. 15v), which conveys very little historical information. Writing at St Gall in the late ninth century, Notker Balbulus pays tribute to Comgall in the entry for Colum Cille in his martyrology and describes him as ‘the illustrious teacher of the most blessed Columbanus’. This line of spiritual descent was almost certainly conveyed to Notker from an Irish source.
Nothing survives of Comgall's writings, though a copy of his rule still existed in the monastery of Fulda in the ninth century. It is likely that the essence of his monastic rule is reflected in Columbanus's rule for monks, with its emphasis on obedience and mortification; fragments of his lost writings may also be preserved in Columbanus's sermons. Comgall died in 602 (Ann. Tig.; AU) or 605 (Ann. Inisf.), worn out, no doubt, by a lifetime of asceticism.