Máel Máedóc Ua Morgair — Malachy in the Latin form — was the son of a senior cleric of Armagh, ordained in 1119 by the reforming archbishop Cellach, and quickly rose to become bishop of Connor (1124), then archbishop of Armagh (1132). His central work was the reform of an Irish Church that had drifted, through centuries of Viking pressure and hereditary clerical succession, from Roman liturgical and canonical norms.
He travelled twice to Rome, met Pope Innocent II, and was made papal legate for Ireland. He introduced the Cistercian Order to Ireland — Mellifont Abbey was founded in 1142 with monks Bernard of Clairvaux sent at Malachy's request — and the Augustinian Canons not long after. His reform of episcopal structures laid the groundwork for the Synod of Kells in 1152 that established the four metropolitan sees still in use.
On his second journey to Rome in 1148 he stopped at Clairvaux to visit Bernard, fell ill, and died there in Bernard's arms on November 2. Bernard wrote his Vita as one of the most famous saint's lives of the twelfth century. The notorious 'Prophecy of the Popes' attributed to him in the 1590s — the list of all popes from 1143 to the end of the world — is a Renaissance forgery and has no genuine connection to him. He was canonized in 1190 — the first Irish saint formally canonized by the Holy See.