The Church of Ireland which is part of the Anglican Communion, is the largest Protestant church on the island of Ireland, and the second largest Protestant faith in Northern Ireland. Established as the Irish equivalent of the Church of England, following the initial break between King Henry VIII and the Holy See, and the subsequent establishment of English state Protestantism under Henry's children, Edward VI and Elizabeth I, the Church of Ireland became the Kingdom of Ireland's established church. It assumed control of Ireland's ancient churches and cathedrals.

Though the religion of a small minority of Irish people, it remained the official religion of Ireland until church disestablishment, facilitated by an Act of Parliament in 1869, came into effect in 1871. Prior to that it had been funded by tithes or local taxes that all, whether Anglican or not, were obliged to pay to it.

The church itself is structured on a model inherited from pre-Reformation times. The Primate of All Ireland is the Archbishop of Armagh, whose seat in the mediaeval cathedral in the city. (The Roman Catholic Archbishop of Armagh also has a victorian cathedral in the city.) The church is organised on diocesan or bishopric lines. Each local priest is called a rector. As with other Irish churches, it did not divide when Ireland was partitioned in 1920, and continues to be governed on an all-island basis. The Archbishop of Dublin, like his Catholic counterpart, is called the Primate of Ireland, in effect the most senior churchman in the Republic of Ireland.

The current Archbishop of Armagh is His Grace, Archbishop Robin Eames. (He is also called Lord Eames, having been appointed to the British House of Lords.)

The new Archbishop of Dublin is His Grace, Archbishop John Neill. His seat is Christ Church Cathedral in Dublin.

Prominent members of the Church of Ireland include or have included

The Church of Ireland has been experiencing major decline in Ireland. Its numbers have dropped significantly in Northern Ireland, where its members now account for only 15% of the population. In the Republic of Ireland, its numbers have been dwindling dramatically, with many congregations consisting almost entirely of elderly people. In recent decades it has closed many of its country churches and some historic churches in towns and cities. Bishoprics have merged, and ancient buildings such as bishops' palaces are being sold. However the 2002 Irish census showed an unexpected increase of 30% in the Church of Ireland's membership in the Republic. That increase, the first in almost a century, was explained by the large number of Anglican immigrants who moved to Ireland, particularly from Africa. With the exception of the Jewish community, practically all major religious faiths other than Roman Catholicism showed a dramatic increase in adherents due to immigration into Ireland.

See also