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.
19th-century history of the Catholic Church in the United States
Between 1820 and 1860, the Irish constituted over one third of all immigrants to the United States. In the 1840s, they comprised nearly half of all immigrants to this nation. American Catholics were not exactly happy to see the new immigrants. Not only did the exponential growth set off nativist alarms among Protestants, they presented problems for the existing Catholic parishes. The wave of immigration from Ireland led to tension between the Irish and the French-dominated American Catholic Church. French Catholics were contemptuous of the Irish.