The History of Irish Immigration

by Derek Reed August 28, 2026

The History of Irish Immigration: From the Great Famine to the Irish Diaspora

Ireland has one of the world's most remarkable stories of emigration. For centuries, people have left Ireland for many different reasons: poverty, religious and political upheaval, lack of opportunity, family circumstances, adventure and the hope of building a better life elsewhere.

But no single event had a greater impact on Irish emigration than the Great Irish Famine of 1845–1852.

During and after the Famine, millions of Irish people left their homeland. They travelled to the United States, Canada, Britain, Australia and other parts of the world, creating Irish communities whose descendants number many millions today.

The history of Irish immigration is therefore also the history of the Irish diaspora — the millions of people around the world who can trace their ancestry back to Ireland.

Irish emigration before the Great Famine

Irish emigration did not begin with the potato blight.

People had been leaving Ireland for generations before 1845. During the seventeenth and eighteenth centuries, Irish people travelled to Britain, North America, the Caribbean and other parts of the world. Some left voluntarily in search of land and opportunity, while others were transported or entered overseas service under very different circumstances.

Large-scale emigration from Ulster became particularly important during the eighteenth century. Many Protestant emigrants of Scottish and English background, often referred to historically as Scotch-Irish, settled in North America. Their descendants would become an important part of American history.

The Library of Congress notes that early Irish immigrants to America included people from Ulster who were attracted by opportunities for land ownership and greater religious freedom.

By the early nineteenth century, emigration had become an established part of Irish life.

Ireland's population was growing rapidly. The population rose from around 4.5 million in 1800 to approximately 8.2 million by 1841. Much of the rural population depended heavily on small plots of land and, particularly among the poorest, on the potato as a staple food.

For many families, emigration was already becoming a way of life.

Why did Irish people emigrate?

There was no single reason why Irish people left.

For some, the attraction was economic opportunity. America offered the possibility — even if it was often difficult to achieve — of earning wages, acquiring land and creating a future for a family.

For others, emigration was connected with religious or political circumstances.

Family connections were also extremely important. Once one member of a family had established themselves abroad, they could send money home to relatives and help subsequent family members make the journey.

This created a powerful chain migration system.

A son might leave Ireland first. He would find work in New York, Boston, Philadelphia or another city. Once established, he might send money for his sister's passage. She could then help another brother or cousin.

Letters and remittances helped connect Irish families across the Atlantic.

For poorer families, however, emigration could be an enormous sacrifice.

Leaving Ireland meant leaving behind parents, brothers, sisters, neighbours and friends. An emigrant might never see home again.

In Ireland, the departure of a young person could therefore be a deeply emotional occasion.

The American Wake became associated with this experience. The emigrant's departure could resemble a funeral, reflecting the possibility that the person leaving would never return. The National Museum of Ireland notes that the custom was known from at least the 1830s.

The Great Famine and mass Irish emigration

Everything changed in the 1840s.

In 1845, potato blight struck Ireland. The potato crop failed repeatedly during the following years, contributing to a catastrophe of starvation, disease, poverty and displacement.

The effects were particularly devastating because so many poor Irish families depended heavily on potatoes for food.

The Famine was not simply a story of a failed crop. Ireland's social and economic structure, poverty, landholding system, access to food and the response of government and landowners all influenced the course and consequences of the disaster.

More than one million people died during the Famine period, while more than one million others left Ireland. The population continued to fall dramatically in the decades that followed.

For many people, emigration was no longer simply a search for a better life.

It became a matter of survival.

1847: "Black '47"

The year 1847 became known as Black '47 because of the extraordinary suffering experienced across Ireland.

Emigration reached enormous levels.

According to historian Ciarán Ó Murchadha, approximately 250,000 people left Ireland during 1847 alone — about twice the number who had left the previous year.

Ports throughout Ireland became crowded with people desperate to escape poverty and starvation.

Some had relatives abroad who could help them. Others had very little money and few possessions.

Many travelled through ports such as Cork, Limerick, Sligo, Westport, Killala and Kinsale. Belfast and Dublin were also important departure points.

The National Museum of Ireland records that during the Famine many emigrants departed from smaller Irish ports, while others travelled through Britain, particularly Liverpool, before crossing the Atlantic.

For anyone interested in the history of Irish immigration, this period is crucial. The Irish communities that developed in North America, Britain and elsewhere were transformed by the enormous movement of people created by the Famine.

The dangerous journey across the Atlantic

The voyage from Ireland to North America could be extremely dangerous.

The ships carrying poorer emigrants were often overcrowded and badly equipped. Conditions were particularly dreadful on some of the vessels that became known as "coffin ships."

Passengers could face inadequate food and water, poor sanitation, disease and extreme overcrowding.

Some ships experienced terrible mortality.

One example was the Elizabeth and Sarah, which sailed from County Mayo in July 1847 with 276 people aboard. The ship was grossly overcrowded, provisions were inadequate and the voyage lasted eight weeks. By the time it reached the St Lawrence River, 42 people had died.

The journey could therefore be almost as frightening as the conditions the emigrants had left behind.

Disease was a particular danger when ships reached North America.

Grosse Île, in the St Lawrence River in Quebec, became one of the most notorious quarantine stations during the Famine. Thousands of Irish emigrants passed through the Canadian quarantine system, and many died there.

The National Archives of the United States has documented individual stories of Famine emigrants who travelled across the Atlantic, including children who were born during the voyage.

Irish immigration to America

The United States became the most important destination for many Irish emigrants.

The National Museum of Ireland estimates that more than six million Irish people emigrated to the United States from 1820 onwards.

The Famine dramatically increased the scale of this migration.

Irish immigrants settled in cities including New York, Boston, Philadelphia, Chicago and other growing urban centres.

They frequently arrived with little money and faced difficult living and working conditions.

Irish immigrants were often employed in poorly paid manual occupations. Women commonly found work as domestic servants, while men worked in construction, factories, docks, railways and other forms of labour.

Over time, however, Irish Americans became increasingly influential in American political, economic and cultural life.

Irish immigrants and their descendants entered the professions, business, public service and politics.

The Irish-American experience was therefore not simply a story of poverty. It was also a story of adaptation, ambition and social mobility.

Irish immigration to Canada

Canada was another major destination, particularly during the Famine.

For emigrants with limited financial resources, travelling to Canada could sometimes be cheaper than travelling directly to the United States.

Many Irish immigrants arrived at ports along the St Lawrence River and settled in Canada. Others subsequently crossed the border into the United States.

The Irish presence in Canada became substantial. By the 1871 Canadian census, almost one quarter of Canada's population was recorded as having Irish ethnicity.

Irish communities developed in cities and rural areas across Canada, leaving a lasting mark on Canadian culture and society.

Irish immigration to Britain

Britain was another major destination for Irish migrants.

The geographical proximity of Ireland and Britain made the journey considerably easier than crossing the Atlantic.

Liverpool became an important gateway for Irish emigrants travelling onwards to North America, while cities such as Manchester, Birmingham, Glasgow and London attracted large Irish populations.

Irish migration to Britain continued long after the Great Famine.

The National Archives in Britain notes that Irish migration to Britain has a long history, although tracing individual migrants can be difficult because there are generally no passenger lists for people travelling from Ireland to Britain.

Dublin itself was also part of this migration story.

The National Archives of Ireland records that in 1911 there were more than 80 cross-Channel sailings each week from Dublin port to Britain. Many people from rural Ireland passed through Dublin on their way to Britain or further overseas.

Irish women and emigration

One of the most distinctive features of Irish emigration was the very large number of women who left Ireland.

During the later nineteenth century, young single women were particularly prominent among emigrants.

The National Museum of Ireland estimates that between 1856 and 1921 approximately half of Irish emigrants were young women.

Many found employment in domestic service, nursing, factories and other occupations.

For families remaining in Ireland, women overseas could become an important source of financial support.

Money sent home by emigrants — known as remittances — helped families pay debts, improve houses, support relatives and sometimes finance the emigration of additional family members.

Emigration therefore became part of the economic structure of many Irish communities.

Emigration continued after the Famine

The Great Famine did not bring Irish emigration to an end.

In fact, emigration continued for generations.

The population decline caused by death and emigration was enormous. The National Museum of Ireland records that Ireland's population fell from almost 8.2 million in 1841 to around 5.4 million by 1871.

Economic difficulties, agricultural problems, evictions and limited employment opportunities continued to encourage people to leave.

Later periods of agricultural depression, including the crises of the late nineteenth century, contributed to further emigration.

For many young Irish people, leaving became almost an expected stage of life.

A village might lose several members of the same family over a period of years.

Eventually, entire communities could become connected to particular destinations overseas.

The Irish diaspora

The result of these migrations was the creation of one of the world's great diasporas.

Today, millions of people in the United States, Canada, Britain, Australia, New Zealand and elsewhere have Irish ancestry.

For descendants of Irish emigrants, discovering the story of an ancestor can be deeply personal.

A passenger list, census entry, marriage certificate, gravestone or family letter can sometimes provide the clue that connects a modern family to an Irish village or town.

Genealogy has therefore become an important way of understanding the history of Irish immigration.

Behind every statistic was an individual.

A young woman leaving Mayo for Boston.

A family leaving Cork for New York.

A labourer travelling from Kerry to Liverpool.

A child arriving in Canada after a dangerous Atlantic crossing.

These individual stories help us understand the human reality behind the enormous numbers.

Why Irish immigration still matters today

The history of Irish immigration is not simply a story about the nineteenth century.

It continues to influence the modern world.

Irish culture, music, literature and political traditions have travelled across the globe. St Patrick's Day is celebrated internationally, while Irish names and family histories can be found in communities thousands of miles from Ireland.

For millions of people, Ireland remains an important part of their family identity.

The story also helps explain why so many visitors come to Ireland looking for their ancestors.

They want to know:

Where did my Irish ancestors live?

Why did they leave Ireland?

What did they experience during the Great Famine?

Which port did they leave from?

What was Ireland like when they left?

The answers can transform genealogy from a list of names and dates into a human story.

Discover the story of Irish emigration

The Great Irish Famine was one of the defining events in the history of Ireland.

It changed the population, economy and landscape of the country — but its impact extended far beyond Ireland.

The millions who left created communities around the world and passed their memories, traditions and Irish identity to future generations.

For anyone researching Irish ancestry, understanding the history of Irish immigration and emigration can provide an important context for discovering what happened to their own family.

Our Great Irish Famine exhibition in Dublin explores the events behind this extraordinary period of Irish history, including the lives of those who experienced famine, eviction, workhouses and emigration.

If your family left Ireland during the Famine or in the decades that followed, visiting the exhibition can help put their story into the wider history of the people who left — and the Ireland they left behind..

A final thought

Every emigrant had a story.

Some left because they wanted opportunity. Others left because they had no realistic alternative. During the Great Famine, many were driven from Ireland by hunger, poverty, eviction and desperation.

They carried very little with them — but they carried their names, memories, traditions and connections to home.

Those connections survived.

And for millions of people around the world today, the search for an Irish ancestor is ultimately a search for a piece of that story...