SENAN (488?–544?), saint and bishop, was son of Gerrgen, who was descended from Conaire I, king of Ireland. He is one of the nine saints of the race of Conaire who are classed apart in the ‘Leabhar Breac’ and the ‘Book of Leinster’ as being held in high esteem in Munster. They are divided into groups of three, each group having a special title. Senan belonged to the last three, the ‘Torches’ as they were termed. Born about 488 in Corcobaskin, co. Clare, he, when arrived at man's estate, was compelled by the local chieftain to join in a foray on the adjoining territory of Corcomroe. But he took no part in their deeds of violence; and when the expedition was defeated and he was taken prisoner, this led to his life being spared. Dissatisfied with this wild life, he resolved to enter a religious community, and for this purpose placed himself under the instruction of Cassidan, whose church was at Irrus, co. Clare. From him he went to St. Natal of Kilnamanagh, near Kilkenny. He is next said to have visited Rome and Tours, and also St. David's in Wales, and to have brought home a copy of the Gospels written by St. Martin. This was known afterwards as ‘Senan's Gospel.’ On the completion of his studies his first settlement was on the Great Island in Cork Harbour, according to the metrical Irish life by Colman, son of Lenin. From this he went to Iniscarra, on the river Lee, where he had not been long settled when Lugaid, chief of the district, demanded tribute from him. This Senan refused, and an angry discussion took place; but in the end the claim was withdrawn at the instance of Lugaid's friends. While here fifty Roman pilgrims arrived in Cork Harbour, many of whom were hospitably received by Senan. We next read of his building a church at Inisluinge, which Lanigan believed to be one of the islands in the Shannon. But this is an error, as it was situated in the parish of Iniscarra, where the ruins of a later structure on the same site still bear the name. Descending the river Lee Senan sailed round the western coast, touching at Inistusker, off the coast of Kerry, where he passed some time. The churches and beehive houses at Olean Senaig, one of the Magharees off the Bay of Tralee, have been attributed to him, but erroneously, as Senach, after whom they are named, is a different person, though he also was one of the famous nine. Passing on to Iniscaorach, or Mutton Island, he finally reached Iniscathaigh, at the mouth of the Shannon, so called from a monster named the Cathach, which he expelled from the island. Here occurred the visit of St. Canair of Bantry to him which has been immortalised by Moore in his ballad of ‘St. Senanus and the Lady.’
Iniscathaigh is reckoned by Keating among the bishoprics of the province of Cashel, and, according to Ussher, it was subsequently divided between the sees of Limerick, Ardfert, and Aghadoe. Its importance is attested by its round tower; and as late as the reign of Elizabeth we find mention of the ‘converbship’ (coarbship) of Iniscathy, to which large revenues appear to have been attached, and which had then passed into lay hands. Senan's fame was chiefly in the west of Ireland, where numerous churches were dedicated to him. He is also the patron of Lansannan in Denbighshire, and Bedwelty in Monmouthshire, and one of the patrons of Lantressant in Anglesey, and is thought to have given his name to Sennen in Cornwall. Bishop Forbes has identified him with the Scottish saint Kerrog and with the French St. Sané, one of the chief patrons of the diocese of Pol de Léon. His golden bell—heaven-sent, as it was believed—was in existence as late as 1834, but is now lost. The ancient poet, Dallan Forgaill, composed a panegyric on him termed the ‘Amra Senain,’ a copy of which is in the ‘Leabhar Breac,’ and another in the Royal Library of Brussels. His day in the calendar is 8 March, which, however, is not that of his death, but of his burial. He is said to have died in 544.
[Bollandists' Acta Sanct. 8 March, i. 759–98; O'Curry's Lectures on the Manuscript Materials of Ancient Irish History, p. 339, and on the Manners and Customs of the Ancient Irish, vol. i. p. cccxxix; Leabhar Breac (facsimile), 241a; MSS. 4190–200, Royal Library, Brussels; Lanigan's Eccl. Hist. i. 444–6, ii. 2 seq., 20, 89–91; BethaShenain, from the Book of Lismore, translated by Whitley Stokes; Anecdota Oxoniensia, Oxford, 1890; Cal. State Papers, Ireland, Elizabeth, 1574–85.]