When I first heard about magic mushrooms as a teenager in the late seventies, the news that psychedelic drugs were sprouting freely across the nation’s playing fields and golf courses seemed like a plot device from some sci-fi fantasy that had somehow succeeded in obtruding into reality. How could this be? The answer came in the form of a thrilling secret history. According to the lore that spread by word of mouth, at festivals and in the photocopied and stapled sheets of the underground press, the mind-altering properties of the Liberty Cap mushroom had been known since time immemorial. They were referenced in the trippy spirals on ancient megaliths, and had formed the core of the Druids’ priestcraft. After they had been driven underground by uptight Christianity and its witch-burnings, their presence continued to be signalled in coded forms, from the gnomic hints in Alice in Wonderland and Victorian fairy lore to the figure of Santa Claus, whose iconography was a folk-memory of the red-and-white toadstool-eating shamans of Lapland. The sixties’ counterculture had amplified these subterranean rumblings in anthems like Jefferson Airplane’s White Rabbit, and now I had become the latest in a lineage of mushroom initiates that stretched back to the dawn of humanity.

I can’t recall quite how much of this I believed at the time – my generation’s motto, after all, was ‘never trust a hippie’ – but it’s still quite a shock to realise not only that that this entire lineage is confabulated, but just how recently this took place. There are enough historical records of accidental mushroom intoxications to make it clear that Liberty Caps have indeed been popping their pixie-capped heads up across Britain for centuries, but no evidence whatsoever for an intentional magic mushroom trip before the 1970s. Although scientists had found Liberty Caps to be hallucinogenic as early as 1963, the hippie sixties came and went without any of its celebrants spotting the free drugs under their noses. At the time that I was being sagely informed that the inhabitants of our islands had been getting high on mushrooms for millennia, the practice was almost certainly in its very first few seasons.

In Shroom, Andy Letcher has cut through this dense tangle of pseudohistory and urban legend with bracing scepticism, clearing the space for an elegant and authoritative telling of the true story that it conceals. He establishes that although fungi have fascinated, inspired and revolted us throughout history, and one source of this fascination has certainly been their strange intoxicating properties, there are only two parts of the world – Mexico and Siberia – where there is clear evidence that these properties have been deliberately sought out and culturally sanctioned. All the rest of the story, he proposes, dates from the early 1950s: the truth that the myths and urban legends conceal is that we, not our prehistoric ancestors, are the true ‘mushroom people’. From full moon parties in Thailand to stalls in Camden Lock, neo-pagan festivals to internet spore-suppliers, there are far more ‘shroomers’ (the word is now in the OED) today than ever before.

The inciting incident for both this modern culture and its modern myths was an article in Life magazine of May 1957 by the international banker Robert Gordon Wasson that told how, in the mountains of Oaxaca, Mexico, he had discovered and participated in a Mazatec Indian mushroom ceremony of the type thought to have been eradicated by Spanish clerics several centuries ago. From Wasson’s remarkable (if overspun) adventures flowed the scientific discovery of the magic mushroom and the presence of its hallucinogenic ingredient, psilocybin, in other related species around the world, including Britain. Yet at the same time Wasson’s enthusiastic but wayward amateur scholarship (egged on by the Golden Boughinspired mythomania of his friend Robert Graves) convinced him that he had discovered the vestigial remains of a universal religious cult of the mushroom – a hypothesis he elaborated in a series of lavish limitededition books, from where it diffused into the emerging drug counterculture.

Letcher brings the same astute eye to his deconstruction of the modern mushroom cult, analysing how its early evangelists, notably Timothy Leary, persuaded a new generation to put a spiritual and life-changing interpretation on an experience that had typically been viewed as a toxic delirium. A retrofitted pedigree of ancient mushroom wisdom clearly served this sales pitch well but, Letcher argues, the mature and diverse culture that has now established itself around the magic mushroom does its credibility no favours by clinging to this litany of self-deception and wishful thinking. ‘If mushrooms really do deliver meaningful experiences’, he observes, ‘then the fact that the practice is a modern one is neither here nor there’. The profusion of mushroom enthusiasts today tells us much less about humanity’s past than it does about our future, and the stubbornness of our desire for adventures that re-enchant the world around us.

Mike Jay is the author of Emperors of Dreams: Drugs in the Nineteenth Century (Dedalus Press)