A book with the title The Age of Intoxication is bound to elicit curiosity, both about the intoxicating agents themselves, and the particular moment in time when their cultural and geographic reach was such as to identify an age. On neither front does Breen disappoint. His deeply researched and compellingly argued study of the early modern emergence of a global trade in a wide range of commodities able to alter the physical and mental states of their consumers is hard to put down. In it we find everything from the excavated journals of European bio-prospectors wandering—often lost—through the tropics, to court verdicts against marginalized healers and apothecary vendors in metropoles such as Lisbon and London; from the fetishized practices of Indigenous shaman on multiple continents, to the reckless self-experimentation of the budding scientists of the Royal Society; and from the wrecked lives of those who became slaves to their addiction, to the company men whose marriage of entrepreneurism, careful attention to rationalized balance sheets, and the copious use of unfree labor birthed a pharmaceutical industry that remains a behemoth in the modern economy. It contains numerous delightful observations, such as that “the Scientific Revolution was more global—and more druggy—than we once thought” (98); or the image conjured up by the section heading, “Jesuits on Drugs” (108). It even corrects a number of common misperceptions about some of the best-known drugs, returning, for example, the origins of the opium poppy to its native habitat in Western European rather than its imaginary literary home in the so-called Orient or its current journalistic home in the mountainous border zones of Central Asia.

In other words, there is much here to take in, and indeed to savor, for scholars and lay readers of history alike. Its subject cannot be pinned down to one scholarly category such as the history of trade, or of consumption, medicine, tropical exploration, health, science, colonial politics, religious division, and the making of racial concepts, to name just the most obvious. Breen's work informs all of these fields, and probably others I have failed to list. His great achievement derives from his comfort moving across their boundaries with both expertise and a keen eye for the unexpected, but the resulting bounty also makes it difficult to pin down his subject for review. I will zero in on just one insight that seems particularly salient, on the topic of intoxicants as for many others of historical interest. In addition to everything else already noted, this is a book about categories and categorization—that most useful of human intellectual activities, and among the most deceptive too.

To make sense of our world we routinely put things into clearly demarcated boxes. We label some things as harmful while others are health-inducing; some as legal, others as illicit; some as moral, others as degenerate, ad infinitum. In addition to spinning a great yarn, full of characters this reader would have happily spent more time with (at the safe remove of the page, of course), what Breen does best is scramble so many of the categories we might prefer to hold stable. He blurs the line between addiction and healing, intoxicants and pharmaceuticals, sorcery and science, risk taking and experimentation, faith and reason, wild and civilized. He forces us to confront the many ways in which the categories are slippery at best, and pure fiction at worst. Not only is this true in the narrow sense for any given botanical substance that might be both poison and medicine depending on context, preparation, and use; but it is true for broader and more amorphous categories such as rationality and superstition. By framing his study on two nominally separated geographic and chronological cases—the Portuguese empire in the sixteenth and seventeenth centuries and the British empire thereafter—Breen disrupts even the seemingly plausible historical divide between a Catholic, traditional Iberian Europe and a Protestant, enlightened, and scientific northwestern Europe. He shows the many ways in which actors at the time moved seamlessly across these two worlds, despite working hard to cover their tracks as they did so, and often misleading us in the process.

To close this review, I return to the intoxicating substances themselves and an episode from my own life history. One set of my grandparents subscribed to what they would have described as religious fundamentals, one aspect of which was a zero-tolerance policy where alcohol was concerned. They would not permit its consumption in their presence, let alone imbibe themselves. Yet, their kitchen cupboard always stocked what they called a medicinal bottle of brandy, and they did this openly, without so much as a flicker of embarrassment. As a young person, this seemingly obvious inconsistency left me bewildered. Breen has explained it perfectly. They had made a category adjustment, one very much in the tradition of the early modern Portuguese and British actors who people Breen's pages.