St. Ives was born at Kermartin, near Tréguier, Brittany, October 17, 1253 and was the son of Helori, lord of Kermartin, and Azo du Kenquis. In 1267, Ives was sent to the University of Paris where he graduated with a degree in civil law, and he then went on to Orléans in 1277 to study canon law. Upon his return to Brittany, having received minor orders, he was appointed as the "official", or ecclesiastical judge, of the archdeanery of Rennes (1280).
In the meantime, he ardently studied Scripture, and there is strong evidence suggesting that he joined the Franciscan Tertiaries sometime later at Guingamp. He was soon invited by the Bishop of Tréguier to become his "official", and accepted the offer in 1284. He displayed great zeal and rectitude in the discharge of his duty and did not hesitate to resist the unjust taxation of the king, which he considered an encroachment on the rights of the Church. Through his charity Ives gained the title of "advocate and patron of the poor." Having been ordained, he was then appointed to the parish of Tredrez in 1285, and eight years later to Louannee, where he died May 19, 1303.
He was buried in Tréguier, and was canonized in 1347 by Clement VI, his feast being kept on May 19.
He is the patron of lawyers, though not, it is said, their model, for — "Sanctus Ivo erat Brito, Advocatus et non latro, Res miranda populo."