The Irish ancestors of US Presidents John F. Kennedy, Ronald Reagan, Barack Obama, and President Joe Biden all emigrated to the United States within 10 years of each other, according to an Irish genealogy researcher. 

Fiona Fitzsimons, a researcher with the Irish Family History Centre, said that the ancestors of the US Presidents had all left for America due to the Famine and that it wasn't surprising that their descendants were now being regularly elected to the White House. 

"Every fourth person either died or emigrated in a six-year period," she told the Irish Times. "So it’s not surprising that from the 1960s through to the present that you’re seeing the descendants of that generation of Irish, who have now become part of the establishment."

She said that the Irish people who arrived in America during the Famine were poor and lacked the connections to get an education.

It took several generations before the Irish who moved to the US during the Famine got a foothold in American society, Fitzsimons said, explaining why there have now been four American presidents with ancestors from the Famine since 1960.

Fitzsimons was commissioned to research President-elect Joe Biden's Irish roots ahead of his visit to Ireland in 2016 and found that Patrick Blewitt and Owen Finnegan, two of Biden's great-great-grandfathers, had left for America from Ballina in Mayo and the Cooley Peninsula in Louth respectively. 

Both the Blewitts and the Finnegans eventually settled in Scranton, Pennsylvania, having left Ireland in the 1840s and Biden has regularly spoken openly and proudly about his Irish roots. 

However, Fitzsimons said that although Biden was deeply proud of Irish roots, they were not as strong as John F. Kennedy's. A number of Kennedy's great-grandparents moved to America during the Famine and Kennedy remained in touch with his family in Ireland, according to Fitzsimons. 

"I don’t think he’s [Biden’s] the most Irish. JFK, before he ever went across [to Ireland], he didn’t need a genealogist because he was in touch with the family. They remained in touch with the family," she told the Irish Times. 

On the other hand, she said that genealogists were surprised by Barack Obama's Irish roots because they had been forgotten about by both the President and his Irish family. 

Fitzsimons additionally said that there have been some 22 American presidents with Irish heritage but that most of them have never been mentioned alongside the likes of Kennedy or Biden because they came from an Ulster-Scots background. 

She said that the narrow definition of Irishness during the 20th century meant that only presidents of a Catholic and rural background have excluded other presidents with Irish roots from the conversation. 

*Originally published in November 2020. Updated in October 2022.