St. Patrick received his mandate from the Pope Celestine to evangelise Ireland. But after St. Patrick died, the ecclesial set up in Ireland took a more monastic direction, as the diocesan model established by Patrick faded into the background. There was rapid growth of monastic centres that became beacons of light for the Irish faithful. The consecrated bishops played only a subsidiary role to the more powerful abbots at the major monastic centres around the country. The diocesan system was slow to be re-established, particularly as Ireland was never conquered by the Roman empire, which suited the diocesan format being based somewhat on the roman rule template.
The seeds of reformation
There was a big change in the middle ages. For example, the King of Munster and Leinster, Muirchertach Mor O’Briain was present at the Synod of Rath Breasail in 1111 which formally re-inaugurated the diocese system into Ireland, as the church finally moved away from a monastic hierarchy. With King Muirchertach’s presence, the diocese of Killaloe within his territory got an advantageous representation. Then King Muirchertach died in 1119 and the O’Brien dynasty declined. With the synod of Kells in 1152, the size of the diocese of Killaloe was much reduced – Taken from Clare Library.
Nb*: These Synods both laid the foundations and largely formalised the current diocesan model present in Ireland today.
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