Irish Canadians
The first waves of Irish immigrants took place between 1763 and 1880. when ten thousand Irish immigrants arrived on the Island. From 1800 to 1850, "10,000 immigrants from every county in Ireland" had settled in Prince Edward Island and represented 25% of the Island population by 1850.
Irish Americans
In Boston between 1810 and 1840 there had been serious tensions between the bishop and the laity who wanted to control the local parishes. By 1845, the Catholic population in Boston had increased to 30,000 from around 5,000 in 1825, due to the influx of Irish immigrants. With the appointment of John B. Fitzpatrick as bishop in 1845, tensions subsided as the increasingly Irish Catholic community grew to support Fitzpatrick's assertion of the bishop's control of parish government.
In New York, Archbishop John Hughes (1797–1864), an Irish immigrant himself, was deeply involved in "the Irish question"—Irish independence from British rule. Hughes supported Daniel O'Connell's Catholic emancipation movement in Ireland, but rejected such radical and violent societies as the Young Irelanders and the National Brotherhood. Hughes also disapproved of American Irish radical fringe groups, urging immigrants to assimilate themselves into American life while remaining patriotic to Ireland "only individually". In Hughes's view, a large-scale movement to form Irish settlements in the western United States was too isolationist and ultimately detrimental to immigrants' success in the New World.