8 Disturbing Facts About the Irish Potato Famine

A devastating event in Irish history, the Potato Famine altered the course of the Emerald Isle forever.

Published: Nov 11, 2025 written by Kassandre Dwyer, MEd History

Sketch of famine victims and satellite Ireland.

 

In 1845, Ireland experienced a heavy fog and more frequent rains than usual. Farmers were shocked and then horrified when they went to their fields to reap the potato harvest. The tubers were rotten on the vine, and the smell of decay filled the air and hovered over the fields. A major subsistence crop at the time, the loss of this staple and the subsequent famine, known as the Great Hunger, proved devastating to the people, economy, and history of Ireland.

 

1. Potatoes Were Essential to the Irish Populace

variety of potato types
Potatoes remain a dietary staple in many parts of the world today. Source: Agricultural Research Service, USDA via Wikimedia Commons

 

The importance of potatoes to the Irish people in the mid-19th century can not be overstated. English invasions during the 16th and 17th centuries forced thousands of Irish from their land. Many relocated to western Ireland, where the soil was unsuitable for many crops. English immigrants were enticed to relocate and begin farming in the now-available lands of fertile northern Ireland. The English landlords often rented these estates to the Irish, who used this land to grow more valuable crops, such as wheat and corn, that could be used to pay rent. This led to an increased dependence on potatoes, which could be grown in poorer soil and took up little space. An acre of potato plants could produce food for a typical family for a year. At the time of the famine, about two-thirds of Irish farmers produced only potatoes for their families.

 

2. The Famine Was Initiated by a Fungus-Like Organism

phytopathora infestans infected tuber
Phytophthora infestans infects the tubers and plants alike. Source: I.Sáček, senior via Wikimedia Commons

 

The cause of the potato rot and subsequent loss of the crop was a fungus-like organism. Phytophthora infestans, also known as potato blight or late blight, is more common in warm, wet conditions. An organism similar to a fungus called an oomycete, the disease affects the foliage and the potatoes themselves. Leaves rot and shrivel as they turn brown. Some white growth may be observed on the bottom of the leaves. Tubers get reddish-brown spots that soon turn soft and rot. Infected potatoes may not show infection at harvest, but they may rot later while in storage.

 

This disease also affects tomatoes and occasionally related ornamentals such as petunias. It was first recorded in the United States in 1843, and it reached Belgium via a shipment of infected, yet visually normal, tubers. It spread through Europe from there and was first reported in Ireland at the Dublin Botanical Gardens in August 1845. While a year of harvest loss would have been significant, the infection continued, affecting subsequent harvests and exacerbating the effects. Since potatoes are propagated from the tubers themselves, less seed was available, further shrinking potential future crops.

 

3. The Disease Wasn’t the Only Contributing Factor

bridget and children sketch_
An 1849 sketch representing famine sufferer Bridget O’Donnel and two of her children. Source: Illustrated London News via Wikimedia Commons

 

While the disease may have been the inciting factor for the start of the Great Hunger, it was far from the only factor at play. The ongoing tension between Ireland and England created a monoculture subsistence-farming situation that many Irish relied on. Not only was Ireland focused on one crop for subsistence, but generally, one specific variety of potato, the “Lumper,” was grown. A lack of crop diversity meant that the entire crop throughout the country was susceptible to disease. Relief efforts by other countries, particularly England, fell short and have been blamed for perpetuating the famine. Ongoing wet weather created the ideal conditions for the disease to prosper and spread.

 

4. Food Exports Continued Despite Starvation

barley crop awaiting harvest
Barley was one of Ireland’s “money crops” that had the potential to feed the masses. Source: Colin Smith / Geograph Britain and Ireland via Wikimedia Commons

 

During the Great Hunger, up to 75 percent of Ireland’s agricultural soil was dedicated to producing “money crops” like wheat and oats. These crops were exported largely to England.  Despite the fact that these crops had the potential to feed thousands and were unaffected by the blight, exports to England continued throughout the course of the famine. This food was often shipped under military guard as people starved. These exports greatly contributed to the ongoing historical bitterness between Ireland and England.

 

5. Famine Fever Was Rampant

man suffering from typhoid
A Typhoid sufferer. Source: Welcome Images via Wikimedia Commons

 

Exacerbating the effects of spreading starvation, disease was soon moving like wildfire throughout the country. Known collectively as “famine fever,” illnesses such as cholera, typhoid, dysentery, scurvy, and typhus were common, along with pests such as lice. Many people were forced to abandon their homesteads in search of work, and personal hygiene was not a priority in a time of survival. This led to the easy spread of disease.

 

Starvation causes broad immunodeficiency, leaving even the healthiest susceptible to rapidly moving infections. Digestive diseases were common as people turned to foods they didn’t normally consume in order to stay alive, including wild plants and, at times, spoiled food. It is believed that infections accounted for about 50 percent of famine deaths.

 

6. Millions Died, Were Displaced, or Emigrated Elsewhere

emigrants leaving ireland engraving
Emigrants Leaving Ireland by Henry Edward Doyle. Source: An Illustrated History of Ireland from AD 400 to 1800, by Mary Frances Cusack via Wikimedia Commons

 

An accurate count of famine victims is impossible to know. However, it is estimated that approximately 12 percent of Ireland’s population perished—around one million souls. Others were forced to leave home to look for work or sustenance, with many going so far as to leave the country entirely. Between 1845 and 1855, millions left Ireland in search of survival. About two million went to America and Australia, and approximately 750,000 to other areas of Britain. The exodus of the Irish people was the largest single population movement of the 19th century.

 

map of the irish diaspora
A map illustrating the Irish Diaspora. Source: Allice Hunter via Wikimedia Commons

 

The Irish Diaspora resulted in changes that rippled through the history of several countries, including the United States. The Irish who arrived during the Great Hunger period played an influential role in US history, including impacts on the building of the Transcontinental Railroad, the development of major cities, and the early labor union movement. Roughly 15 percent of today’s US citizenry can claim Irish ancestry.

 

famine memorial in dublin
A famine memorial in Dublin. Source: William Murphy via Wikimedia Commons

 

Unfortunately, many were waiting to be transported to their destinations on “coffin ships.” These overcrowded, largely unsanitary ships had captains who simply sought to make a profit. Mortality on these boats ranged from 5 to 30 percent, often from disease caused by poor conditions.

 

7. It Led to One of the Earliest International Fundraising Efforts

great hunger memorial in mass
A memorial to the Great Hunger in Cambridge, Massachusetts, USA. Source: Mincebert via Wikimedia Commons

 

Despite Britain’s lackluster response, other entities from around the globe came together to attempt to alleviate some of Ireland’s suffering. These efforts are often considered one of the earliest international responses to a natural disaster. Fundraising started as early as 1845 and picked up in subsequent years.

 

The city of Calcutta in India sent over 16,500 pounds of relief funds, while Bombay sent 3,000. The Society of Friends, better known as the Quakers, in the United States, collected supplies, including clothes, food, seed, and bedding to send, giving over 200,000 pounds worth of relief to the Irish people. The Choctaw people of the United States, who had suffered their own torment on the “Trail of Tears” just a few years earlier, sent a cash donation (equaling about $5,000 in today’s funds). This initiated a lifelong friendship between the town of Midleton, where the funds ended up, and the Choctaw Nation. In 2017, a sculpture commemorating the Choctaw’s gift was dedicated in a Midleton park.

 

8. Ireland’s Population Has Never Recovered

ireland via nasa sattelite
Ireland via satellite, 2023. Source: Jacques Descloitres, NASA via Wikimedia Commons

 

As the Great Hunger caused unprecedented death and displacement, it took a toll on Ireland’s human population. Pre-famine population levels were rising, quadrupling between 1700 and 1845. As the famine began, Ireland’s estimated population was over eight million people. By 1851, the Irish population, which had been predicted to be nine million by that time, was reduced to approximately six million. As the famine wound down, the population of the country continued to decline and would remain declining for more than a century, finally ceasing in 1951. Political and economic instability led to continuing emigration long after the famine was considered over.

 

crowd to see obama moneygall
A 2011 crowd in Moneygall, Ireland, watching for visiting US President Barack Obama. Source: White House via Wikimedia Commons

 

2022 census data showed the first population levels over five million since 1851, a 7.6 percent increase from the last data in 2016. In addition, these increases were reflected across all of the country’s counties. As of 2023, Ireland’s population has still not recovered to pre-famine levels, hovering at 5.2 million people.

photo of Kassandre Dwyer
Kassandre DwyerMEd History

Kassie is a farmer and freelance writer with a passion for history and teaching others about it. A National Board Certified Teacher, she holds a MEd in History, a MEd in Curriculum & Instruction, and a BS in Sustainable Agriculture & Animal Science. She is particularly interested in the ability of history stories to teach empathy to the next generation, and telling the stories of often overlooked historical perspectives or hidden truths. Kassie has special interests in the history of America’s Indigenous peoples, war, maritime history, and the “wild west.”