Religion in the Republic of Ireland
The predominant religion in the Republic of Ireland is Christianity, with the largest church being the Roman Catholic Church. The Irish constitution says that the state may not endorse any particular religion and guarantees freedom of religion.
History of Christianity in Ireland
The established church in Ireland underwent a period of more radical Calvinist doctrine than occurred in England. James Ussher (later Archbishop of Armagh) authored the Irish Articles, adopted in 1615. In 1634, the Irish Convocation adopted the English Thirty-Nine Articles alongside the Irish Articles. After the Restoration of 1660, it seems that the Thirty-Nine Articles took precedence; they remain the official doctrine of the Church of Ireland even after disestablishment.