The predominant religion in the Republic of Ireland is Christianity, with the largest denomination being the Catholic Church. The Constitution of Ireland says that the state may not endorse any particular religion and guarantees freedom of religion.
In the 2022 census, 69% (3.5 million) of the population identified as Catholic. The next largest group after Catholic was "no religion" at 14%. The second largest Christian denomination, the Church of Ireland (Anglican), declined in membership for much of the twentieth century, but remained largely static (at 2% of the population) between the 2016 and 2022 census. Other significant Protestant denominations are the Presbyterian Church in Ireland, followed by the Methodist Church in Ireland. The country's Orthodox Christian, Hindu and Muslim populations have experienced significant growth in recent years, due chiefly to immigration, with Orthodox Christianity being the fastest growing religion in Ireland.
Politics
Originally, the 1937 Constitution of Ireland gave the Catholic Church a "special position" as the church of the majority, but also recognised other Christian denominations and Judaism. As with other predominantly Catholic European states, the Irish state underwent a period of legal secularisation in the late twentieth century. In 1972, the article of the Constitution naming specific religious groups, including the Catholic Church, was deleted by the fifth amendment of the constitution in a referendum.
Article 44 remains in the Constitution. It begins:
The article also establishes freedom of religion (for belief, practice, and organisation without undue interference from the state), prohibits endowment of any particular religion, prohibits the state from religious discrimination, and requires the state to treat religious and non-religious schools in a non-prejudicial manner.
Education
Despite a large number of schools in Ireland being run by religious organizations but funded by the state, a general trend of secularism is occurring within the Irish population, particularly in the younger generations.
Many efforts have been made by secular groups to eliminate the rigorous study in the second and sixth classes, to prepare for the sacraments of Holy Communion and confirmation in Catholic schools. Parents can ask for their children to be excluded from religious study if they wish. However, religious studies as a subject was introduced into the state administered Junior Certificate in 2001; it is not compulsory and deals with aspects of different religions, not focusing on one particular religion.
In October 2020, general secretary of Education and Training Boards Ireland Paddy Lavelle confirmed that multidenominational state secondary schools, called State's Education and Training Boards (ETBs) - formerly called vocational schools - were going to phase out a set of Catholic influences such as mandatory graduation masses, displaying Catholic symbols only, and visits from diocesan inspectors, as described in the 'framework for the recognition of religious belief/identities of all students in ETB schools'.
Christianity
Christianity is the largest religion in the Republic of Ireland based on baptisms. Irish Christianity is dominated by the Catholic Church, and Christianity as a whole accounts for 82.3% of the Irish population. Most churches are organised on an all-Ireland basis which includes both Northern Ireland and the Republic of Ireland. Catholic Church in Ireland Protestantism in Ireland Presbyterian Church in Ireland Methodist Church in Ireland Eastern Orthodoxy in the Republic of Ireland The Church of Jesus Christ of Latter-day Saints in Ireland Irish travellers have traditionally adopted a very particular attitude to the Catholic Church, with a focus on figures such as "healing priests". More generally a tradition of visions continues, often outside of Church sanction.
Evangelical movements have recently spread both within the established churches and outside them. Celtic Christianity has become increasingly popular, again both within and outside established churches.
The patron saints of Ireland for Catholics and Anglicans are Saint Patrick, Saint Brigid and Saint Columba. Saint Patrick is the only one of the three who is commonly recognised as the patron saint. Saint Patrick's Day is celebrated in Ireland and abroad on 17 March.
Eastern Orthodoxy in Ireland is represented mainly by recent immigrants from Eastern European countries, such as Romania, Russia, or Ukraine, and accounts for 1% of the population.
In 2022, 40 percent of Catholics stated they attend church.