The Great Famine ( Irish : An Gorta Mór lit: The Great Hunger [ 1 ] or An Drochshaol , lit: The Bad Life ) was a period of starvation, disease and mass emigration between 1845 and 1852 [ 2 ] during which the population of Ireland was reduced by 20 to 25 percent. [ 3 ] Approximately one million of the population died and a million more emigrated from Ireland's shores. [ 4 ] The proximate cause of famine was a potato disease commonly known as late blight . [ 5 ] Although blight ravaged potato crops throughout Europe during the 1840s, the impact and human cost in Ireland—where a third of the population was entirely dependent on the potato for food—was exacerbated by a host of political, social and economic factors which remain the subject of historical debate. [ 6 ] [ 7 ]
The famine was a watershed in the history of Ireland . [ 8 ] Its effects permanently changed the island's demographic, political and cultural landscape. For both the native Irish and those in the resulting diaspora , the famine entered folk memory [ 9 ] and became a rallying point for various nationalist movements . Modern historians regard it as a dividing line in the Irish historical narrative, referring to the preceding period of Irish history as "pre-Famine."