The chronology of the Great Famine (Irish: An Gorta Mór or An Drochshaol, litt: The Bad Life) documents a period of Irish history between 29 November 1845 and 1852 during which time the population of Ireland was reduced by 20 to 25 percent. The proximate cause was famine resulting from a potato disease commonly known as late blight. 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 but which also produced an abundance of other food – was exacerbated by a host of political, social and economic factors which remain the subject of historical debate.