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
Half of the Irish immigrants in the colonial era came from the Irish province of Ulster while the other half came from the other three provinces of Ireland (Leinster, Munster, and Connacht). While scholarly estimates vary, the most common approximation is that 250,000 migrated to the United States from 1717 to 1775. By 1790, approximately 400,000 people of Irish birth or ancestry lived in the United States. These early immigrants were overwhelmingly members of the Protestant minority in Ireland who descended from Scottish and English colonists and colonial administrators who had settled the Plantations of Ireland, the largest of which was the Plantation of Ulster. In Ireland, they are referred to as the Ulster Scots and the Anglo-Irish respectively (and as the Ulster Protestants collectively), and while they intermarried to some degree, they almost never intermarried with the native Irish Catholic population (in part because intermarriage between Protestants and Catholics was banned by the Penal Laws during the Protestant Ascendancy), and in turn, the Irish Catholics almost never converted to Protestant churches during the Reformation. (For that matter, intermarriage between Protestants and Catholics in Northern Ireland has remained rare into the 21st century and remains highly stigmatized due to the Troubles and the dissident Irish Republican campaign that has followed them.)