Learn about Irish emigration and the mass exodus during The Famine:

Irish emigration reached unprecedented proportions during the famine as people fled from hunger and disease. Between 1845 and 1851, over 1,500,000 people emigrated from Ireland — more than had left the country in the previous half century. Many famine emigrants went initially to British North America (now Canada) because of fare structure and government regulations, but the majority subsequently settled in the United States.