St. Brendan of Ardfert and Clonfert, known also as Brendan the Voyager, was born in Ciarraighe Luachra, near the present city of Tralee, County Kerry, Ireland, in 484; he died at Enachduin, now Annaghdown, in 577. He was baptized at Tubrid, near Ardfert, by Bishop Erc. For five years he was educated under St. Ita, “the Brigid of Munster”, and he completed his studies under St. Erc, who ordained him priest in 512. Between the years 512 and 530 St. Brendan built monastic cells at Ardfert, and at Shanakeel or Baalynevinoorach, at the foot of Brandon Hill. It was from here that he set out on his famous voyage for the Land of Delight. The old Irish Calendars assigned a special feast for the “Egressio familiae S. Brendani”, on 22 March; and St Aengus the Culdee, in his Litany, at the close of the eighth century, invokes “the sixty who accompanied St. Brendan in his quest of the Land of Promise”. Naturally, the story of the seven years’ voyage was carried about, and, soon, crowds of pilgrims and students flocked to Ardfert. Thus, in a few years, many religious houses were formed at Gallerus, Kilmalchedor, Brandon Hill, and the Blasquet Islands, in order to meet the wants of those who came for spiritual guidance to St. Brendan.
Having established the See of Ardfert, St. Brendan proceeded to Thomond, and founded a monastery at Inis-da-druim (now Coney Island, County Clare), in the present parish of Killadysert, about the year 550. He then journeyed to Wales, and thence to Iona, and left traces of his apostolic zeal at Kilbrandon (near Oban) and Kilbrennan Sound. After a three years’ mission in Britain he returned to Ireland, and did much good work in various parts of Leinster, especially at Dysart (Co. Kilkenny), Killiney (Tubberboe), and Brandon Hill. He founded the Sees of Ardfert, and of Annaghdown, and established churches at Inchiquin, County Galway, and at Inishglora, County Mayo. His most celebrated foundation was Clonfert, in 557, over which he appointed St. Moinenn as Prior and Head Master. St. Brendan was interred in Clonfert, and his feast is kept on 16 May.
The Akathist and Office to St Brendan can be found here.