Catholic Church in Ireland
In the 2016 Irish census 78.3% of the population identified as Catholic in Ireland; numbering approximately 3.7 million people. Unlike Catholics in the United States, Ireland has seen a significant decline from the 84.2% who identified as Catholic in the 2011 census.
Protestant Irish nationalists
All the various denominations of Protestantism in Ireland have had members involved in nationalism. Historically the Anglican Church of Ireland and the Presbyterian Church of Ireland have been the largest Protestant churches, and this remains the situation across the island of Ireland. The largest Protestant denomination is the Church of Ireland (having roughly 365,000 members, making up around 3% of the population of the Republic of Ireland, 15% of Northern Ireland, and 6.3% of the whole of Ireland), followed by the Presbyterian Church, with a membership of around 300,000, accounting for 0.6% of people in the Republic and 20% in Northern Ireland (6.1% of Ireland's population).