The population of Ireland reached its peak of over 8 million in 1845, the year that saw the beginning of the potato blight. This rapid population growth, from approximately 4.4 million in the late 18th century, had been made possible by the introduction of the potato. It was a cheap source of nutrition, but an over reliance on this single crop proved disastrous. When the potato crop failed, the poor starved.Exacerbating the crop failure was British rule. The British and the ruling gentry were Protestants, while the vast majority of the population were Catholics. Denied basic political and civil rights because of religion, the poor now also died needlessly. During the Potato Famine, Ireland exported food. Moreover, taking advantage of the calamity, landed gentry gained more land as they evicted the starving families from their homes.The Great Famine caused the starvation of one million, the emigration of a million more and has repercussions that are felt today in Irish society. Continued emigration and general societal disruption lowered the population to 2.8 million in 1961. The total population of the whole of Ireland in 2012, the north(still under British rule) and the Republic , was approximately 6.4 million. Despite having the highest birth rate in the European Union, and migration from several countries, Ireland has never fully recovered from the Great Famine. The population remains lower than 1845.

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