The Church of Ireland is a Christian church in Ireland, and an autonomous province of the Anglican Communion. It is organised on an all-Ireland basis and is the second-largest Christian church on the island after the Roman Catholic Church. Like other Anglican churches, it has retained elements of pre-Reformation practice, notably its episcopal polity, while rejecting the primacy of the pope.

The Anglican Communion is the third largest Christian communion after the Roman Catholic and Eastern Orthodox churches. Formally founded in 1867 in London, the communion has more than 85 million members within the Church of England and other autocephalous national and regional churches in full communion. The traditional origins of Anglican doctrine are summarised in the Thirty-nine Articles (1571). The archbishop of Canterbury in England acts as a focus of unity, recognised as primus inter pares, but does not exercise authority in Anglican provinces outside of the Church of England. Most, but not all, member churches of the communion are the historic national or regional Anglican churches.