Newfoundland communities are ‘most Irish’ outside Ireland, genetic study finds

In some cases, 80 per cent of the population are of Irish heritage going back hundreds of years

Parts of the Canadian province of Newfoundland have a majority population which is genetically Irish going back almost 200 years, new research confirms.

Newfoundland is almost unique in having a settler population which has been barely diluted by further waves of migration.

Approximately 25,000 Irish and English emigrants came to the province in the late 18th and early 19th centuries, mostly due to the rich fishing grounds off the coast. As a result of its geographical isolation and economic setbacks, most of the descendants of people now living in Newfoundland are related to the original settlers.

Newfoundland has a population of just 500,000, though it is larger than the island of Ireland. A large majority of the population is based on the Avalon peninsula, which includes the capital St John’s. By and large, the English settled on the north of the Avalon peninsula, with the Irish on the south.


The coastal towns on the south of the Avalon peninsula are part of what is know as the Irish Loop. Many people there have a discernible Irish accent though neither they nor their ancestors have lived in Ireland for generations.

A study by RCSI University of Medicine and Health Sciences, based in Dublin, and Sequence Bio, a genomics and precision medicine company based in St. John’s, Newfoundland and Labrador, has produced the most detailed genetic analysis of people living in the Canadian province to date.

By studying the genetic profiles of 1,807 volunteering individuals from Newfoundland and comparing them to genetic studies in Ireland and England, scientists showed that a significant proportion of the population can be traced back to settlers who primarily migrated from southeast Ireland and southwest England around three centuries ago.

In the case of some settlements around the south of the Avalon peninsula, there is Irish ancestry in 80 per cent of the population.

According to the 2006 census, 20 per cent of the population is of Irish ancestry but the real figure is likely to be much higher than that as most people in the province put down their ancestry as Canadian.

Most Irish emigrants to Newfoundland came originally from the counties of Wexford, Waterford and Kilkenny because of their trade links with what was then a British colony.

Report co-author, Dr Edmund Gilbert, a lecturer at the School of Pharmacy and Biomolecular Sciences in RCSI, said the genetic make-up of the island is unique and remarkable, which is why it is of great interest to geneticists.

Another factor he said was remarkable is how little intermingling there has been between the English and Irish settlers with both communities inclined to keep to themselves.

“The English and Irish communities are what is called as ‘stratified’ which means there are English communities and there are Irish communities, even with hundreds of years of potential mixing,” he said.

This also correlates with religion with those who are Catholics identifying strongly genetically with their Irish ancestry while those have English ancestry are predominantly Anglican by denomination.

The study, titled “Newfoundland and Labrador: A mosaic founder population of an Irish and British diaspora from 300 years ago”, has been published in the nature journal, Communications Biology.

Ronan McGreevy

Ronan McGreevy

Ronan McGreevy is a news reporter with The Irish Times