The Great Potato Famine, Ireland, 1840s. The poor farmers in Ireland were dependent upon potatoes to survive. Interestingly, despite the huge number or starving people on the island, huge numbers of crops (such as corn and grain) were exported for profit rather than used at home.
The Great Famine was a period of mass starvation, disease and emigration in Ireland between 1845 and 1852. During the famine Ireland's population dropped by 20–25 percent, one million people died, and a million more emigrated from the island. The proximate cause of the famine was a potato disease commonly known as potato blight. The blight was so devastating because one third of the Irish population was entirely dependent on the potato for food.