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.
Protestantism in Ireland
In 1991, the population of the Republic of Ireland was approximately 3% Protestant. The figure in the same geographical area was over 10% in 1891, indicating a fall of 70% in the relative Protestant population over the past century.