This is a book about everything that happened in the second half of the nineteenth century: not just the appearance of alternative forms of spirituality, but also science, technology, imperialism, steam power, racism, the selling of birds mummified in guano in Liverpool shops, Marx's carbuncles, and a great many other, usually interesting, topics. The book is structured around abrupt crosscutting between roughly simultaneous events: in 1865, two months after the assassination of Lincoln in Washington, DC, Wagner's Tristan und Isolde was first performed in Munich; in 1871, a week after the first performance of Wagner's Siegfried, Darwin's Descent of Man appeared; in 1882, as Nietzsche was finishing The Gay Science, Madame Blavatsky was off to Tibet; and so on. These parallels are interesting, but the lack of continuous exposition obscures the argument of the book. And, in fact, since the argument is never clearly stated, it is left to the reader to discover what it is. The following is my attempt.

Nineteenth-century modernity, the age of scientific materialism, was the age in which the Christian God “died,” ceased to be a living presence. But what Emerson called the “religious instinct” is innate and ineliminable. And so there was a growing demand for a new form of spirituality. Emerson and Thoreau found it in nature mysticism, but that is an individual rather than collective experience. The first of the new “faiths” (8) was spiritualism, which first appeared in upper New York State in 1848. Through seances that involved mysterious tapings, typewriters, and Ouija boards, the bereaved were able to communicate with departed souls. Madame Blavatsky, who invented theosophy, condemned spiritualism as a mere parlor game, but she herself was by no means above parlor games, games that involved, for instance, holes in ceilings through with mysterious letters sometimes fluttered down. Blavatsky sought to combine American spiritualism with the European “occultism” of Éliphas Lévi, the self-declared magus who used Tarot cards not to foretell fate, but rather to control it. From Lévi, Blavatsky adopted the notion that while all religions express the same truth, the oldest and most profound are Zoroastrianism and the religion of the Indian Vedas. Rightly, I think, Green sees some of Nietzsche's works as fishing in the same waters as Blavatsky and Lévi: the bombastic Thus Spoke Zarathustra is another attempt to found a new religion for a new age, a work designed, Nietzsche said, to replace the Bible.

Evolutionary thought plays an unusual role in The Religious Revolution, appearing, in the main, not so much as the enemy of religion but as a source of new, secular religions: social Darwinism, utopian Marxism, eugenics, Nietzsche's quest for the superman, and the antisemitism of, for instance, Gobineau and Wagner. It is odd to find antisemitism presented as a form of spirituality, but as Green illuminatingly points out, nineteenth-century antisemitism was not mere hatred of Jews, but consisted, rather, in a totalizing worldview that provides an explanation of every aspect of the “intolerable confusion” of modern life (270). The QAnon conspiracy theory, one suspects, performs a similar function in the present age.

As Green emphasizes, almost all the founders of the new spirituality were tricksters and frauds, eager to enrich themselves in the spiritual vacuum left by the “death of God.” Yet paradoxically, many of their followers were decent (if credulous) people, given to new age things such as lose clothing, vegetarianism, socialism, feminism, teetotalism, and the cultivation of beauty. Like Blavatsky, Lévi, and Emerson, they revered the wisdom of the East. Given the spiritual poverty of the West, the turn to the East was a natural development. It was made possible by the translations of Sanskrit texts that were just beginning to become easily available as a biproduct of European colonialism.

Was there a “religious revolution” in the nineteenth century? Not really. Despite secularism, the spirituality of mainstream Christianity surely retained many more adherents than any of its rivals. Moreover, insofar as the alternative “faiths” had a theology, it was always parasitic upon the mainstream. Spiritualism is indebted to Christian theology for the departed souls who appear to the medium, and many of its adherents were Quakers. And theosophy's doctrine of spiritual enlightenment, karma, and reincarnation is taken straight out of Buddhism—to which Blavatsky converted. Theology—and therefore “religion,” to the extent that a religion requires a theology—remained (and remains) the prerogative of the great, traditional religions. As Nietzsche observed more or less accurately, “Two thousand years have come and gone—and not a single new God!”

Green is a polymath, but not an infallible one. Though he did believe in animal rights, Schopenhauer was not a “militant vegetarian” (157); Lamarck was not a “biological mystic” who believed in a “mysterious ‘life force’ compelling species to climb the  ladder of development” (96), but rather an anti-mystical mechanist who believed in the inheritability of acquired characteristics; and there is no real evidence that Nietzsche was gay. A strange omission is Rudolf Steiner, the least scurrilous of the new-agers. Steiner broke away from theosophy to create both anthroposophy and the Waldorf schools that continue to educate talented individuals such as Jonathan Miller, Harrison Ford, Paul Newman, and Sandra Bullock.