The Irish Potato Famine, also called the Great Potato Famine, Great Irish Famine or Famine of 1845, was a key event in Irish history. While estimates vary, starvation and epidemics of infectious diseases probably killed about 1 million Irish between 1845 and 1851, while another 2 million are estimated to have left the island between 1845 and 1855. Many of these migrants headed for North America, where they established communities in cities like New York and Boston.

Causes of the Famine

The famine’s origins lay in the spread of a fungus that caused a disease in potatoes called late blight. The potato was the staple food crop in Ireland, providing 60 percent of the food needs of the population. The blighted 1845 potato harvest partially failed, and subsequent harvests from 1846 through 1849 were almost completely destroyed. In the absence of potatoes, prices for other foodstuffs rose, placing them beyond the reach of poor families.

British Famine Policy

At the time of the famine, all of Ireland was part of the United Kingdom, but British policy toward the famine-hit Irish did little to alleviate their suffering. British policy was marked by inaction -- some British leaders characterized the famine as a judgment from God on the lazy and rebellious Irish, while others claimed it was not the government’s role to interfere in the Irish economy by, for example, halting exports of grain grown in Ireland or directly feeding the hungry through soup kitchens.

Population Movements Within Ireland

The starvation and poverty of the famine years led to large-scale population movements within Ireland in addition to spurring emigration. Research by three British and Irish academics using 1841 and 1851 census figures has shown how some local districts, particularly in rural areas of western Ireland, experienced a population loss of over 60 percent in 10 years, while others, particularly urban areas, gained population.

The Hazards of Emigration

Desperation forced hundreds of thousands of Irish to seek a better life in North America. The journey, often undertaken in unsafe and vastly overcrowded vessels known as “coffin ships,” was risky in itself. Conditions on the ships were appalling; on one 1847 voyage from the port of Cobh in County Mayo, 276 passengers in steerage class shared 32 berths without any sanitary facilities, and 42 passengers died during the prolonged eight-week journey to Canada. According to Irish historian William Henry, as many as a fifth of the Irish who attempted the trans-Atlantic crossing during the famine years died en route from disease or hunger. If the migrants arrived in America, they endured squalid housing and anti-Irish bigotry.