SINCE the Second Vatican Council in 1962, the Roman Catholic church has striven to adapt to the modern world. But in the West—where many hoped a contemporary message would go down best—believers have left in droves. Sunday mass attendance in England and Wales has fallen by half from the 1.8m recorded in 1960; the average age of parishioners has risen from 37 in 1980 to 52 now. In America attendance has declined by over a third since 1960. Less than 5% of French Catholics attend regularly, and only 15% in Italy. Yet as the mainstream wanes, traditionalists wax.

Take the Latin mass, dumped by the Vatican in 1962 for liturgies in vernacular languages. In its most traditional form, the priest consecrates the bread and wine in a whisper with his back to the congregation: anathema to those who think openness is the spirit of the age. But Father John Zuhlsdorf, an American priest and blogger, says it challenges worshippers, unlike the cosy liberalism of the regular services. “It is not just a school assembly,” he says.

Others share his enthusiasm. The Latin Mass Society of England and Wales, started in 1965, now has over 5,000 members. The weekly number of Latin masses is up from 26 in 2007 to 157 now. In America it is up from 60 in 1991 to 420. At Brompton Oratory, a hotspot of London traditionalism, 440 flock to the main Sunday Latin mass. That is twice the figure for the main English one. Women sport mantillas (lace headscarves). Men wear tweeds.

But it is not a fogeys’ hangout: the congregation is young and international. Like evangelical Christianity, traditional Catholicism is attracting people who were not even born when the Second Vatican Council tried to rejuvenate the church. Traditionalist groups have members in 34 countries, including Hong Kong, South Africa and Belarus. Juventutem, a movement for young Catholics who like the old ways, boasts scores of activists in a dozen countries. Traditionalists use blogs, websites and social media to spread the word—and to highlight recalcitrant liberal dioceses and church administrators, who have long seen the Latinists as a self-indulgent, anachronistic and affected minority. In Colombia 500 people wanting a traditional mass had to use a community hall (they later found a church).

A big shift came in 2007 when Pope Benedict XVI formally endorsed the use of the old-rite Latin mass. Until that point, fondness for the traditional liturgy could blight a priest’s career. The cause has also received new vim from the Ordinariate, a Vatican-sponsored grouping for ex-Anglicans. Dozens of Anglican priests have “crossed the Tiber” from the heavily ritualistic “smells and bells” high-church wing; they find a ready welcome among traditionalist Roman Catholics.

The return of the old rite causes quiet consternation among more modernist Catholics. Timothy Radcliffe, once head of Britain’s Dominicans, sees in it “a sort of ‘Brideshead Revisited’ nostalgia”. The traditionalist revival, he thinks, is a reaction against the “trendy liberalism” of his generation. Some swings of pendulums may be inevitable. But for a church hierarchy in Western countries beset by scandal and decline, the rise of a traditionalist avant-garde is unsettling. Is it merely an outcrop of eccentricity, or a sign that the church took a wrong turn 50 years ago?