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.
Christianity in Ireland
In 1861, only the west coast and Kilkenny had less than 6% Protestant population. Dublin and two of the border counties had over 20% Protestant. By 1991, however, all counties had fewer than 6% Protestants, with four having less than 1%. There are no counties in the Republic of Ireland which have experienced a rise in the relative Protestant population over the period 1861 to 1991. The counties which retain the highest proportion of Protestants tend to be those which started off with a large proportion. In Northern Ireland, only counties Londonderry, Tyrone and Armagh have experienced a significant loss of relative Protestant population, though at a lesser rate than in the Republic.