Christianization of Ireland

Later tradition ascribes the Christianization of all Ireland to St Patrick, but historical evidence suggests that Patrick led a British church mission to Ulster and Connaught, while the Gaulish church evangelized Leinster and Munster. Indeed, Ireland was not fully Christianized until some time in the 6th century, long after Patrick's death.

Gaulish and British missions The history of Ireland's Christianization is very vague because later historiographers rewrote the tradition to exalt Patrick's (and Armagh's) role. Patrick was not the first missionary bishop to visit Ireland; he was preceded by Palladius in the 5th century, who was sent by the Gaulish church at the request of Christians in Ireland. As this request came while he was in Britain, it is likely that these first Irish Christians were mostly, like Patrick, British slaves. Little is known of Palladius' mission. Tradition claims that he left (or died) soon after arriving in Ireland and that Patrick was sent as his successor, but this is probably another Patrician revision. Palladius came from the Gaulish church, as did other important figures such as Secundius (Dunshaughlin, County Meath), Auxilius (Killashee, County Kildare), and Isernius (Kilcullen, County Kildare). Later tradition views these three as Patrick's subordinates, but they worked in Leinster, whereas Patrick's writings show that he remained in Ulster (and possibly Connaught). This suggests that they were in continuity with Palladius' Gaulish mission, while Patrick spearheaded a British mission in Ulster and Connaught. Other 5th-century figures (about whom we know relatively little) are Ibar (Wexford), Ailbe (Emly, County Tipperary), Mel (Ardagh, County Limerick), and Mac Cuilinn (Lusk, County Dublin).

Development of Irish Christianity Gradually, the British and Gaulish missions declined in importance as a distinctively Irish Christianity developed that emphasized monastic abbots/abbesses rather than bishops. This was largely a result of the radical changes in Irish power structures during the 5th century. The old provinces were gradually being replaced by a less static dynastic structure that did not favour an episcopal system based around the traditional centres of power (such as Tara Hill). The monasteries gained such control that some episcopal settlements, such as Armagh, became monastic centres.