The Vanishing Irish

I t’s quaint to think about now, but in 1954, American Catholic journalist John A. O’Brien commissioned a collection of essays by important Irish writers — Seán Ó Faoláin, John D. Sheridan, and others — called The Vanishing Irish. It was about what they perceived as a baffling trend, the startling low fertility of Ireland, then at 3.4 children a woman. Ireland currently has a fertility rate hovering around 1.4 children per woman.

Ireland’s own Department of Finance commissioned a report in 2025 called the Future Forty report featuring demographic projections. Because of immigration and population momentum, Ireland’s total population looks set to increase from 5.5 million to nearly 8 million by 2065. This would represent a return to the pre-famine population level or above it. Ireland’s 19th-century famine and the giant waves of emigration have meant that Ireland is the only country on earth to currently have a lower population now than it did in 1830.

But that news is mixed. By 2065, there would be 98 people in the labor force for every 100 not working. The old-age dependency ratio, which is the number of people at pension-receiving age (over 65) compared to the number of working-age people (15-65), goes from 23.1 pensioners per 100 workers in 2022 to 55.2 pensioners per 100 workers in 2065. Maybe most alarming is that even if Ireland achieves a population of 8 million in 2065, it would still have fewer teenagers than it did in 2022.

These projections make for some pretty astonishing outcomes. Ireland used to be one of the most homogenous countries on earth until 1990. Now, nearly one in five residents in Ireland is foreign-born. The projections also rely on estimates that net migration will add only 53,000-58,0000 people a year. Right. But net migration has been higher for years now — it was at 79,300 in 2024. More questionable are the fertility-rate assumptions. The report assumes that native fertility rates will slide to 1.3 by 2038, then hold at a low of 1.2.

This is a very rosy assessment, considering that Irish fertility is already dropping to 1.4 children currently. Most national and U.N. demographers have had these assumptions that fertility will stop dropping and begin holding steady. But there’s no good evidence for this. Looking for hope, some may point to South Korea, which crashed years ago through 1.0 births per woman down to 0.75 and has since “rebounded” to 0.80.  There are even early signs in the first half of 2026 that births are up 15.4 percent. June 2026 had a fertility rate of 0.88 — but this is a small-cohort effect. The children of 1991–1995 represent an “echo boom” — as they are reaching marrying age.

Strangely, despite Ireland’s becoming on paper one of the richest countries in the world, the problems behind its low fertility are much the same ones as were described in the 1950s in a country that today would be considered a very high and healthy fertility nation. The writers of The Vanishing Irish identified that fertility within marriage was relatively healthy — but that the problem the Irish faced was a culture in which people were afraid to marry until they had achieved secure incomes or access to property. Rural Ireland is perhaps a surprising pioneer in the capstone vision of marriage.

My own theory is that there are two underrated reasons behind the compounding effect of infertility. The first is that fertility is memetic — or socially contagious. Building a family is a difficult enterprise, and when young people see fewer of their peers doing it, their confidence in doing it themselves drops along with it. Secondly, infertility is compounding because larger and younger families are themselves the basis on which larger and younger families are built.

Delayed fertility over two generations, like a mother who has her first child at 35 and then daughters who have their first children at 35, means that the youngest generation has a grandparent who is simply much older and much less well-positioned to contribute to the raising of children. This lack of grandparent involvement has become an almost cliched complaint among Millennial parents. Parents, too, delaying their fertility into middle age, find themselves with less energy to play, to govern, to parent.

Of course, having grown up with a family tree that was already pruned of cousins and siblings, modern parents simply have a smaller kin network to rely on for support. Social, moral, and economic resources used to be accessible to parents through the institution of the family but are now bought at exorbitant prices in the marketplace, whether that is childcare, access to compatible social networks, or organized play and activity.

This way of life is plainly unsustainable over the long term and cannot continue compounding. Devoting more economic resources to older and older generations will mean less innovation and risk-taking, precisely when we need more economic growth to support more people who are not in the workforce, and who themselves are not making the investment in posterity to raise another productive generation.