In 1845 a water mold named Phytophthora Infestans which afflicts potato and tomato plants began to spread across Europe, killing potatoes from Sweden to Spain. “The potato blight caused crisis everywhere it appeared in Europe,” writes my guest Padraic X. Scanlan; “in Ireland, it caused an apocalypse.” In 1845, a third of the United Kingdom’s population lived in Ireland; an 1841 census had counted a population of 8.2 million. In the next six years, 1 million of them would die from famine related causes; another 1.5 million had emigrated. The 1851 census totaled the Irish population at 6.5 million, and the population of Ireland would continue to decline for another 100 years. “Although the labouring poor ate potatoes throughout northern and western Europe, only Ireland experienced demographic collapse during and after the blight pandemic.” And the consequences of the famine were more than demographic. It frayed or destroyed communal and familial relationships, and must have led to long-lasting psychological trauma.

Padraic X. Scanlan is an associate professor at the Centre for Industrial Relations and Human Resources and the Centre for Diaspora & Transnational Studies at the University of Toronto. The author of two previous books, his latest is Rot: An Imperial History of the Irish Famine, and it is the subject of our conversation today.