The 2021 Northern Ireland Census marked the first time since records began where the Catholic share of the population was larger than the combined Protestant share. In 2021, over 42 percent of the population classified themselves as Catholic or from a Catholic background, in comparison with 37 percent classified as Protestant or from a Protestant background. Additionally, the share of the population with no religion (or those who did not answer) was 19 percent; larger than any individual Protestant denomination. This marks a significant shift in demographic and societal trends over the past century, as Protestants outnumbered Catholics by roughly 2:1 when Northern Ireland was established in the 1920s. Given the Catholic community's historic tendency to be in favor of a united Ireland, many look to the changing religious composition of the population when assessing the potential for Irish reunification. Religion's historical influence A major development in the history of British rule in ireland was the Plantation of Ulster in the 1600s, where much of the land in the north (historically the most rebellious region) was seized from Irish Catholics and given to Protestant settlers from Britain (predominantly Scots). This helped establish Protestant dominance in the north, created a large section of the population loyal to the British crown, and saw a distinct Ulster-Scots identity develop over time. In the 1920s, the republican movement won independence for 26 of Ireland's 32 counties, however, the six counties in Ulster with the largest Protestant populations remained part of the UK, as Northern Ireland. Following partition, structural inequalities between Northern Ireland's Protestant and Catholic communities meant that the Protestant population was generally wealthier, better educated, more politically empowered, and had better access to housing, among other advantages. In the 1960s, a civil rights movement then emerged for equal rights and status for both sides of the population, but this quickly turned violent and escalated into a the three-decade long conflict now known as the Troubles.

The Troubles was largely fought between nationalist/republican paramilitaries (mostly Catholic), unionist/loyalist paramilitaries (mostly Protestant), and British security forces (including the police). This is often described as a religious conflict, however it is more accurately described as an ethnic and political conflict, where the Catholic community generally favored Northern Ireland's reunification with the rest of the island, while the Protestant community wished to remain in the UK. Paramilitaries had a large amount of support from their respective communities in the early years of the Troubles, but this waned as the conflict progressed into the 1980s and 1990s. Demographic and societal trends influenced the religious composition of Northern Ireland's population in these decades, as the Catholic community had higher fertility rates than Protestant communities, while the growing secularism has coincided with a decline in those identifying as Protestant - the dip in those identifying as Catholic in the 1970s and 1980s was due to a protest and boycott of the Census. The Troubles came to an end in 1998, and divisions between both sides of the community have drastically fallen, although they have not disappeared completely.

Conducting a wide-ranging survey of Catholic adults living in Britain aimed to provide a detailed study of personal faith, social attitudes, and political engagement within a significant religious minority in Britain with distinctive historical roots and in which 'tribal' feelings of belonging have been strong. The core topics would consist of personal faith, religiosity, and associational involvement in parish life; attitudes towards leadership and governance within the institutional church; attitudes on social and moral issues; and political attitudes and engagement. It would be thematically and analytically rich, providing a comprehensive portrait of contemporary social, religious, and attitudinal heterogeneity amongst Catholics.

By undertaking this large-scale survey, an important and distinctive contribution would be made to the sociology of religion in Britain in general and to the study of its Catholic population in particular. The survey was conducted online by Savanta ComRes, from October to November 2019. This is a cross-sectional dataset, based on interviews with 1,823 self-identifying Catholics adults in Britain (aged 18 and over).

This dataset provides Census 2021 estimates about the religion or religion brought up in of the usual resident population of Northern Ireland, by broad age bands. The estimates are as at census day, 21 March 2021.

The census collected information on the usually resident population of Northern Ireland on census day (21 March 2021). Initial contact letters or questionnaire packs were delivered to every household and communal establishment, and residents were asked to complete online or return the questionnaire with information as correct on census day. Special arrangements were made to enumerate special groups such as students, members of the Travellers Community, HM Forces personnel etc. The Census Coverage Survey (an independent doorstep survey) followed between 12 May and 29 June 2021 and was used to adjust the census counts for under-enumeration.

'Religion' indicates religion, religious denomination or body.

'Age' is age at last birthday.

'Catholic' includes those who gave their religion or their religion brought up in as Catholic or Roman Catholic.

Quality assurance report can be found here

This table provides Census 2021 estimates that classify people by Country of birth (12 categories) by Religion (8 categories) for Northern Ireland. The table contains 96 counts.

The census collected information on the usually resident population of Northern Ireland on census day (21 March 2021). Initial contact letters or questionnaire packs were delivered to every household and communal establishment, and residents were asked to complete online or return the questionnaire with information as correct on census day. Special arrangements were made to enumerate special groups such as students, members of the Travellers Community, HM Forces personnel etc. The Census Coverage Survey (an independent doorstep survey) followed between 12 May and 29 June 2021 and was used to adjust the census counts for under-enumeration.

Notes

1. 'EU' is the European Union and is as defined on census day (21 March 2021).
2. People who gave 'Cyprus' as their country of birth are included within the 'Europe: Other EU countries' category.
3. 'Europe: Other Non-EU countries' includes United Kingdom (part not specified) and Ireland (part not specified).
4. 'Religion' indicates religion, religious denomination or body.
5. 'Catholic' includes those who gave their current religion as Catholic or Roman Catholic.

Quality assurance report can be found here

This table provides Census 2021 estimates that classify people by National identity (8 categories) by Religion or religion brought up in for Northern Ireland. The table contains 32 counts.

The census collected information on the usually resident population of Northern Ireland on census day (21 March 2021). Initial contact letters or questionnaire packs were delivered to every household and communal establishment, and residents were asked to complete online or return the questionnaire with information as correct on census day. Special arrangements were made to enumerate special groups such as students, members of the Travellers Community, HM Forces personnel etc. The Census Coverage Survey (an independent doorstep survey) followed between 12 May and 29 June 2021 and was used to adjust the census counts for under-enumeration.

'Religion' indicates religion, religious denomination or body. 'Catholic' includes those who gave their current religion as Catholic or Roman Catholic.

Quality assurance report can be found here

This source hails from the earlier years of large-scale survey research in Britain, with the electronic data file created following scanning of and data capture from original survey returns. The data collection provides insight into the lifestyles and religiosity of urban young people, predominantly working-class, at the dawn of the affluent society. It comprises a stratified random sample survey of the religious, social and associational lives of young people aged 15-24 in urban England in 1957. It was designed and fielded by the Newman Demographic Survey, a private research institute directed by religious sociologist Tony Spencer, in collaboration with Young Christian Workers, a faith-based youth organisation. The investigators aimed to yield a sample of English urban youth which would include at least 1000 Catholic respondents, representing all English Catholic dioceses. 8196 was achieved, of which following some apparently random data loss 5834 were of sufficient quality for scanning and data capture in 2010. The survey instrument consisted primarily of closed-form items piloted in Gateshead, Highgate and Manchester, and was designed following correspondence with specialist survey experts: Len England (1901-1999), Director of Mass Observation; Leslie Austen, director of Social Surveys (Gallup Poll) Ltd; and W.L. Readman at the National Food Survey at the Ministry of Agriculture, Fisheries and Food. John Mandeville of the British Tabulating Machine Company, a British-based company operating under licence to IBM, also provided advice to the survey investigators. The electoral register was used as the sampling frame, using a version of the 'nth page' method. To prevent interviewer fatigue, about half of the respondents (70% of Anglicans) completed a short version of the questionnaire, covering items on leisure and religious belief, while the remainder completed a longer version including items on associational memberships, schooling, religious attendance and practice, marital status, and parental country and religion of origin. Some written-in responses (on leisure, religious affiliation, associational memberships and occupation) have been captured. Design and post-stratification weights have been calculated for users.

These datasets provide datasets on the religion people connect or identify with (their religious affiliation), whether or not they practise or have belief in it, by age and sex using Census 2021 data.

Religious groups in the detailed religion classification

The counts for religious groups identified in the Religion (detailed) in England and Wales dataset are a representation of those who chose to write in their religion. Some people may have chosen to describe a denomination of one of the tick-box responses (for example, Catholic as a denomination of Christian or Orthodox as a denomination of Jewish) through the "Any other religion" write-in response option.

2011 Religion data

In 2011, an error in the processing of census data led to the number of usual residents in the “Religion not stated” category being overestimated by a total of 62,000 for the following three local authorities combined: Camden, Islington, and Tower Hamlets.

In February 2015, the ONS published corrected figures for estimates based on the tick-box classification. However, it could not be corrected for the detailed religion classification because the processing and relationships with other output variables are so complex.

For this reason, only apply comparisons for these three local authorities to the tick-box classification, using the corrected figures set out in the ONS 2011 Census products: Issues and corrections notice.

For this publication, where corrected figures for the tick-box classification from the 2011 Census are available, they have been used. Where they are not (for single year of age by sex), the ONS has used data from the CT0291_2011 commissioned table.

This statistic presents the average weekly attendance figures for the Church of England in London from 2012 to 2017. During this period there has been a net decrease of 12 thousand people attending church in London, a trend which is also reflected in the weekly attendance figures for the whole of England.

This dataset provides Census 2021 estimates that classify usual residents in Northern Ireland by their religion, and by broad age bands.

The census collected information on the usually resident population of Northern Ireland on census day (21 March 2021). Initial contact letters or questionnaire packs were delivered to every household and communal establishment, and residents were asked to complete online or return the questionnaire with information as correct on census day. Special arrangements were made to enumerate special groups such as students, members of the Travellers Community, HM Forces personnel etc. The Census Coverage Survey (an independent doorstep survey) followed between 12 May and 29 June 2021 and was used to adjust the census counts for under-enumeration.

'Religion' indicates religion, religious denomination or body.

'Age' is age at last birthday.

'Catholic' includes those who gave their current religion as Catholic or Roman Catholic.

Quality assurance report can be found here

Political inequality between Catholic and Protestant communities was one of the key social issues in the 1960s in Northern Ireland, and the civil rights campaign that emerged in the pursuit of equal representation would eventually give way to the 30-year conflict that became known as the Troubles. Following Irish independence from Britain in the 1920s, the island of Ireland was partitioned and the six counties of Ireland with the largest Protestant populations remained in the UK as Northern Ireland. At the time of partition, the north's population was roughly two-thirds Protestant, one-third Catholic, which gave political dominance to unionist parties - generally seen as those representing Protestant communities' interests. However, despite the numerical advantage, the political system was rigged to further extend this political advantage. University students and business owners (both groups were overwhelmingly Protestant), were granted a second vote in Stormont (Northern Ireland's parliament) elections. In local elections, only ratepayers (i.e. the heads of households) and their spouses could vote - this excluded many Catholic adults who were living in multi-generational households, which was a symptom of Northern Ireland's housing shortage and inequalities in housing allocation between the two communities. Moreover, this meant that voters who paid rates (NI's council tax) on multiple properties could vote several times, on top of additional votes for business owners and companies, which were more likely to be Protestant. In addition to voting inequalities, districts were gerrymandered in favor of unionist parties. In combination, these factors often proved decisive in swinging elections to give unionist parties victory in Catholic-majority areas.

This dataset provides Census 2021 estimates that classify usual residents in Northern Ireland by their religion. The estimates are as at census day, 21 March 2021.

The census collected information on the usually resident population of Northern Ireland on census day (21 March 2021). Initial contact letters or questionnaire packs were delivered to every household and communal establishment, and residents were asked to complete online or return the questionnaire with information as correct on census day. Special arrangements were made to enumerate special groups such as students, members of the Travellers Community, HM Forces personnel etc. The Census Coverage Survey (an independent doorstep survey) followed between 12 May and 29 June 2021 and was used to adjust the census counts for under-enumeration.

This table reports the categories for which there are 10 or more usual residents. Where there are fewer than 10 usual residents for any category, these have been reported in a residual group which may or may not contain 10 or more usual residents in total.

'Religion' indicates religion, religious denomination or body. 'Catholic' includes those who gave their current religion as Catholic or Roman Catholic.

Quality assurance report can be found here

This table provides Census 2021 estimates that classify people by Economic activity by Religion (8 categories) for Northern Ireland. The table contains 112 counts.

The census collected information on the usually resident population of Northern Ireland on census day (21 March 2021). Initial contact letters or questionnaire packs were delivered to every household and communal establishment, and residents were asked to complete online or return the questionnaire with information as correct on census day. Special arrangements were made to enumerate special groups such as students, members of the Travellers Community, HM Forces personnel etc. The Census Coverage Survey (an independent doorstep survey) followed between 12 May and 29 June 2021 and was used to adjust the census counts for under-enumeration.

'Religion' indicates religion, religious denomination or body. 'Catholic' includes those who gave their current religion as Catholic or Roman Catholic.

Quality assurance report can be found here

British Army troops were sent to Northern Ireland in 1969 in order to de-escalate tensions between the dominant Protestant and minority Catholic communities during the civil rights movement. Operation Banner, as it came to be known, then lasted until 2007, making it the longest continuous deployment in British military history. The army was initially welcomed by Catholic communities, who felt they would offer protection from what they viewed as a corrupt and sectarian police service, however this quickly changed after a series of interactions between the army and Catholic community turned violent. The army would then become the primary target of republican (predominantly Catholic) paramilitaries throughout the Troubles, and around 750 of those killed in the conflict were from the British Armed Forces (including the UDR). The Ulster Defence Regiment The Ulster Defence Regiment (UDR) was also established in 1970 in an attempt to relieve the police (the RUC) of any militaristic duties, and to replace the Ulster Special Constabulary (also known as the B Specials), who were not trusted by the wider Catholic community. During the Troubles, regular army forces were mostly made up of soldiers from mainland Britain, while the UDR drew from the local population - originally intended to represent local demographics in terms of religious representation, the UDR was almost entirely made up of Protestants within a few years.