Irish Immigration to Canada The Irish began immigrating to North America in the 1820s, when the lack of jobs and poverty forced them to seek better opportunities elsewhere after the end of the major European wars. When the Europeans could finally stop depending on the Irish for food during war, the investment in Irish agricultural products reduced and the boom was over. After an economic boom, there comes a bust and unemployment was the result. Two-thirds of the people of Ireland depended on potato harvests as a main source of income and, more importantly, food. Then between the years of 1845 and 1847, a terrible disease struck the potato crops.