However, during the 12th century a stricter uniformity in the Western Church was enforced, with the diocesan structure introduced with the Synod of Ráth Breasail in 1111 and culminating with the Gregorian Reform which coincided with the Anglo-Norman invasion of Ireland.

Aside from this independence, Gaelic Ireland was a highly decentralised tribal society, so mass conversion to a new system would prove a drawn out process even as the Christian religion began to gradually move into the island.

Instead, medieval Gaelic historians in works such as the Lebor Gabála Érenn attempted to link the historical narrative of their people (represented by the proto-Gaelic Scythians) to Moses in Egypt.

[note 1] Furthermore, according to the Lebor Gabála Érenn, the lifetime of Jesus Christ was synchronised with the reigns of Eterscél, Nuadu Necht and Conaire Mór as High Kings of Ireland.

Apart from these, the figure most associated with the Christianisation of Ireland is Patrick (Maewyn Succat), a Romano-British nobleman, who was captured by the Gaels during a raid, when the Roman rule in Britain was in decline.

Patrick contested with the druí, targeted the local royalty for conversion, and re-orientated Irish Christianity to having Armagh, an ancient royal site associated with the goddess Macha (an aspect of An Morríghan), as the preeminent seat of power.

Monks also founded monasteries on smaller islands around Ireland, for instance Finnian at Skellig Michael, Senán at Inis Cathaigh and Columba at Iona.

Dál Riata in what is now Argyll was geopolitically continuous with Ireland and Iona held an important place in Irish Christianity, with Columban monastic activities either side of the North Channel.

The Columbans of Iona were the most resistant of the Irish, holding out until the early 700s, though their satellite Lindisfarne was pressured into changing at the Synod of Whitby in 664, partly due to an internal political struggle.

Indeed, the Cornish had been converted by Irish missionaries: patron saint Piran (also known as Ciarán) and a nun princess Ia; who gave her name to St. Ives; were foremost.

The zeal and piety of the Church in Ireland during the 6th and 7th centuries was such that many monks, including Columbanus and his companions, went as missionaries to Continental Europe, especially to the Merovingian and Carolingian Frankish Empire.

One of the major figures associated with the Gregorian Reform in Ireland was Máel Máedóc Ó Morgair, also known as Malachy, who was an Archbishop of Armagh and the first Gaelic Irish saint to undergo a formal canonisation process and official proclamation.

Máel Máedóc was closely associated with Bernard of Clairvaux and introduced his Cistercian order from France into Ireland with the foundation of Mellifont Abbey in 1142.

In 1155, John of Salisbury, Secretary to the Archbishop of Canterbury (then Theobald of Bec), visited Benevento where the first English Pontiff, Pope Adrian IV (Nicholas Breakspear) was reigning.

Fearful that the Norman barons would set up their own rival Kingdom and wanting Ireland himself, Henry II landed at Waterford in 1171, under the authority of Laudabiliter (ratified by Pope Alexander III).

In the following years, Norman-descended churchmen would now play a direct role within the Irish Church as the political Lordship of Ireland was established, though many Gaelic kingdoms and their dioceses remained too.

[11] The Templars had their Principal at Clontarf Castle until their suppression in 1308[12] and received land grants from various patrons; from the de Laceys, Butlers, Taffes, FitzGeralds and even O'Mores.

The effect of the Act of Supremacy 1558 and the papal bull of 1570 (Regnans in Excelsis) legislated that the majority population of both kingdoms to be governed by an Anglican ascendancy.

The Maynooth Grant of 1845, whereby the British government attempted to engender good will to Catholic Ireland became a political controversy with the Anti-Maynooth Conference group founded by anti-Catholics.

For many decades, Catholic influence (coupled with the rural nature of Irish society) meant that Ireland was able to uphold family-orientated social policies for longer than most of the West, contrary to the laissez-faire-associated cultural liberalism of the British and Americans.

[24] After the results of both the 2015 same-sex marriage and the 2018 abortion referendums, Úna Mullally, a liberal journalist who writes for The Guardian claimed that "the fiction of Ireland as a conservative, dogmatically Catholic country has been shattered".

We have throughout been careful to keep in mind and to make allowance for the particular points of view of Roman Catholics in regard to education so far as known to us, and it has been our desire to refrain as far as we could from recommending any course which might be thought to be contrary to their wishes.

[30][31][32] There are also many religious orders, which include: Augustinians, Capuchins, Carmelites, Fathers of the Holy Ghost, Dominicans, Franciscans, Jesuits, Marists, Missionaries of Charity, Oblates, Passionists, Redemptorists, and Vincentians.

A few resident Eastern Catholic priests serve mainly immigrant communities, with supervision split between an apostolic visitor of the same church based abroad and a Latin-church bishop in Ireland.

As a consequence of the famine, the Parish Mission's Movement commenced that would lead to a stricter observance of Catholicism in Ireland as well as the push for reform of healthcare and education which would later be expanded into the overseas missionary work.

[36] Initially inspired largely by Cardinal Newman to convert the colonised peoples of the British Empire,[citation needed] after 1922 the church continued to work in healthcare and education what is now the Third World through its bodies such as Trócaire.

Éamon de Valera's 1937 constitution, while granting freedom of religion, recognised the "special position of the Holy Catholic Apostolic and Roman Church".

The United Nations Committee on the Rights of the Child in Geneva asked Ireland's minister for children, James Reilly, to explain the continuation of preferential access to state-funded schools on the basis of religion.

[49] War-time censorship by the government for security was strict and included the church; when bishops spoke on aspects of the war, they were censored and treated "with no more ceremony than any other citizen".

[51] Several reports detailing cases of emotional, physical and sexual abuse of thousands of children while in the pastoral care of dozens of priests have been published in 2005–2009.