The adjective Celtic has been used to sell so many things—from books and music to jewelry to alternative spiritualities—that a canny reader might be forgiven for passing over a book called The Last of the Celts as one more piece of fluff. That would be a mistake, for in this angry, elegiac and meticulously researched book, Londoner Marcus Tanner, former assistant foreign editor of the Independent and author of books on Croatia and Ireland, casts a starkly revealing light on the cresting wave of popular Celtophilia.

This is certainly not the first such wave. Tanner prefaces the personal travelogue that is the backbone of his account with a brief history of the 1,500-year-old pattern in which invading cultures (Saxon, Norman, Anglican, Victorian, postmodern) rediscover Celtic people and remake the Celtic story for their own ends. But this wave may well be the last. As Tanner puts it:

All the Celtic revivals of the past and present have been predicated on the existence, somewhere, of people for whom these languages, traditions and beliefs actually mean something. As they finally disappear and the Celtic sea, having retreated into disconnected pools, reduces to puddles after which there may be nothing, we enter a new territory.

At its center this is a book about the importance of language and about what is lost when a language dies. The story begins with Tanner’s search for the burial stones of his Welsh ancestors. When he discovered the stones in an abandoned churchyard in Wales, he is disquieted because he cannot read the Welsh inscriptions: “I felt like an invisible wall separated me from these long-dead Tanners, a wall not merely of death but of culture.” So out of a deep sense that it is only through its language that a culture can be fully understood, Tanner learned Welsh. He then embarked on a quest through the Celtic lands—not only those of Wales, Scotland, Ireland, Cornwall, Brittany and the Isle of Man, but also remote “New World” colonies in Nova Scotia and Patagonia, where Celtic people have kept their language intact over several generations.

Tanner’s findings will probably be discouraging for readers interested in all things Celtic. But his discoveries might satisfy those who are fed up with fad Celticism. In popular centers of Celtic pilgrimage like Iona and various other “church-run souvenir shops” he sees “copious quantities of supposedly Celtic gear—from prayers, charms, jewellery and cures to recipes—alongside books on Celtic saints fronted by interlace patterns.” These, he suggests, have little to do with any real Celtic culture, past or present. Rather, their presence is a result of the needs of Christian churches that “hug the Celts to their bosom these days because what they call Celtic spirituality implies a set of favorable cultural references, including a less hierarchical and less sexually censorious form of religion. These they hope will resolve many of the dilemmas that they face in modern Western society.”

Tanner suggests that “the real inheritors of the Celtic spiritual tradition . . . were the Methodists in Cornwall, the Calvinist Methodists in Wales, and the Free Church in Scotland, none of them known for mysticism, an interest in herbal remedies, tolerance of pagan traditions or liberal attitudes towards sex.” These findings are a warning to those who treat the Celtic tradition as a kind of Rorschach inkblot into which they can read their own concerns.

The conclusion Tanner draws after his travels is that most of the communities that speak a living Celtic language are now almost entirely overwhelmed by a surrounding dominant language and culture, usually English. Cornish and Manx have been extinct for centuries. Gaelic-speaking Scots have declined to less than 1 percent of the Scottish population. In Wales, Gaelic-speakers are down to 18 percent.

Ireland is superficially the healthiest linguistic community, with over a million Gaelic-speakers, but this does not present a hopeful picture because it reflects a political inflation of Irish identity in contradistinction to English identity; Irish is a genuine living language, Tanner suggests, to barely 1 percent of the population. At best, he concludes, “the overall picture is of a weak dam that has quite suddenly collapsed, leaving the floodwater to wash over the already water-logged land behind it.”

The Last of the Celts is far more about people than statistics. We follow Tanner on a very human quest—to a bed and breakfast in Brittany, for example, where he found an elderly couple who spoke Breton to each other. He listened, “conscious that a language and a culture was fading away and that it was a privilege to be catching the sound.” We trail him to a deserted church in Wales, where William Morgan served over four centuries ago and published, in 1588, a Welsh translation of the Bible. Morgan’s gift kept Welsh language and culture intact till well into the 20th century. And we hear the pain and anger with which Tanner listened to the young people in Cape Breton in Canada whose grandparents spoke mainly Gaelic. Now the youth converse in American slang without even a trace of an accent from the dying language of their ancestors:

Like young Americans, they interpolate their sentences with the repeated use of the word “like” and emphasize the ultimate or penultimate syllable, so that many of their sentences finish with a “like awesome!” . . . or with a “like, you know, incredible!” . . . The Americans seem to have had the last laugh in Nova Scotia, sucking the Canadians back into the homogenised goo of American popular culture.

Ultimately this fine book is a lament for the disappearance of the local, the particular and the unique beneath the “homogenized goo” of a larger culture—whether global, English, or American. The disappearance of the communities that speak the Celtic languages is paralleled by the decline of other cultures all over the world.

Still, the book and the situation are not entirely without hope. In his travels Tanner spoke with many who were working valiantly to make their languages and cultures genuinely live. “A new mood of confidence may just possibly emerge” from such efforts, he suggests. And perhaps it will.

“Europe needs living Celtic languages,” Tanner contends. “Their disappearance has obviously impoverished the people who spoke them,” and “their extinction also impoverishes the rest of the continent and the world.” However, perhaps because he fears slipping into the kind of projection he sees in the latest Celtic “revival,” he is reluctant to say much of anything about the actual content of the Celtic culture and outlook that the languages kept alive. He refrains, for example, from any discussion of the massive accumulation of cultural data in Alexander Macpherson’s 19th-century collection of prayers, spells, chants and songs from the still-intact Gaelic-speaking cultures of the highlands and islands of Scotland. No amount of use or misuse by popular Celticism can drain that work of its authenticity or power.

Yet in the very passion, eloquence and determination with which Tanner pursues his own quest, we can glimpse some of the appeal of the language and culture he honors in The Last of the Celts.