Bridget O’Donnel and children. Illustrated London News, December 22, 1849 

The Great Famine in Ireland, running roughly from 1845 to 1852, depopulated the British colony. The main source of food for subsistence farmers, the potato, failed due to a blight that hit the crop across the globe. Around one million died from starvation and related illness; the same number migrated. The poorest of the Irish refugees entered New England through French-speaking Canada, since transportation between British holdings was cheaper than between Great Britain and the United States. Many, weakened by the effects of long-term malnutrition, became sick in the crowded, unsanitary ships, referred to as coffin ships, and died. Grosse Isle, near Quebec City, served as a quarantine island for arrivals. The long rows of mass graves filled with the bodies of those who made it to North America but no further remain.