Final answer:
The Irish Potato Famine occurred in Ireland between 1845-1850, which led to over a million deaths and caused massive emigration due to potato blight and monocultural farming practices.
Step-by-step explanation:
The potato famine of 1845-1850, known as the Irish Potato Famine, occurred in Ireland. Phytophthora infestans, the pathogen causing the potato blight, devastated the Irish potato crop, which was a staple food for the majority of the population. This agricultural catastrophe resulted in over a million deaths due to starvation and compelled another million people to emigrate, many to the United States. The British government's inadequate response to the famine revealed deep-seated prejudice against the predominantly Catholic Irish population and exposed the dangers of low crop diversity. Ireland's population was significantly reduced from over 8 million in 1841, and has not fully recovered to this day. This historical event underlines the importance of agricultural variety and has had a lasting impact on both Ireland and the global community.