Each Pentecost weekend, thousands of young pilgrims walk the 100 kilometres from Paris to Chartres, singing Latin hymns and carrying banners of the Virgin Mary. Again this year, the event grew so large it had to close registrations: 19.000 pilgrims were counted the by organisers.
What makes the Chartres pilgrimage remarkable is not merely its scale, but its demographic profile. The participants are overwhelmingly young, devout, and part of larger-than-average families. Many walk as part of multi-generational groups—parents with five, six, or even ten children—reflecting a striking divergence from prevailing European fertility trends. These pilgrims are not only religious; they belong to a growing subculture of practising Catholics who marry young, reject contraception, and embrace high fertility as a moral and spiritual vocation. In demographic terms, this means that actively religious minorities, though small in absolute numbers, are exerting an outsized influence on the future population base. The pilgrimage thus offers more than a spectacle of faith—it reveals a quietly expanding demographic that is both culturally resilient and biologically ascendant.
The decline of religion in Western Europe has long been treated as a fait accompli. Churches are empty, affiliation drops, and faith recedes to the private sphere. Yet this narrative overlooks a persistent—and increasingly potent—countercurrent. New data show that religion, particularly when actively practised, continues to shape Europe’s most intimate decision: whether to have children.
Recent demographic research by Nitzan Peri-Rotem reveals that religious practice remains a powerful determinant of fertility across France, Britain, and the Netherlands—three of Europe’s most secular societies. In France and the Netherlands especially, the fertility gap between practising believers and the non-affiliated has grown across generations. While mass religious identity declines, small but resilient cores of believers maintain, even increase, their reproductive edge.



