The world's history measured out in coffee cups

The Devil's Cup: coffee, the driving force in history by Stewart Lee Allen (Canongate Books, £12.99)

What's the connection between food-based books in the publishing industry and the 36 bus? You wait an age for one and then five arrive at once - cod, apples, potatoes, nutmeg, and now coffee. But why now? In part, all of these books take commodities that the global food industry has rendered mundane in the West, and make them exotic again.

What's the connection between food-based books in the publishing industry and the 36 bus? You wait an age for one and then five arrive at once - cod, apples, potatoes, nutmeg, and now coffee. But why now? In part, all of these books take commodities that the global food industry has rendered mundane in the West, and make them exotic again.

Merely scratching the historical surface reveals their intimate links to global interactions and fearsome conflicts. In an era of unprecedented globalisation, the commodity narratives of the age of imperial expansion offer an important perspective on the present. Perhaps, most appealingly, they provide an entrée into the realm of economic and imperial history without the elephantine weight of academic discourse. In the microcosm is the macrocosm.

Stewart Lee Alan certainly delivers on the microcosm. He cuts a caffeine-fuelled arc that runs from coffee's Ethiopian origins, through its Arabian distillation, across its European domestication, before terminating in a cross-country search for the worst cup of American coffee.

In east Africa, the bean was crushed and chewed. Its stimulating effects made it a favourite for spiritual experiences. Carried by the Arabian slave trade across the Red Sea to the Yemeni city of Aln-Makkha, it was transformed into Mocha. With alcohol off limits, little wonder coffee became the wine of Islam. By the time it had made it to the Ottoman Empire, it had become the pre-whirling drink of choice for Sufi mystics.

But it was in Istanbul that coffee's capacity to quicken the wit emerged, encouraging the sultan's subjects to converse on public policy. Indeed, the 16th-century Ottoman élite became so alarmed at the political intoxication of coffee drinkers that they inaugurated the first war on drugs, closing down coffee-houses and persecuting drinkers and suppliers.

Allen follows the Turks to the gates of Vienna, where military defeat saw them head back to the Balkans without their supplies. Thus began the Viennese coffee-house. Within a century, European élites had adopted the bean. They turned their sharpened minds to commercial success in London's coffee houses, revolution in French cafés, and colonisation and planting in Brazil and Indonesia.

In Munich, Allen gets back to the macrocosm and elaborates his coffee-centric theory of history. It runs something like this. Islamic, Ottoman and then European civilisations all prospered immediately after acquiring this recreational drug. In Europe's case, the previous five or six centuries had seen the continent subsist on ergot-infected wheat and enormous quantities of beer. So 500 years of drunkenness created a civilisation afflicted by the effects of alcohol: sloppy reasoning, credulity, excessive emotion. Coffee sobered up and straightened out the continent so it could get on with the business of business, empire and revolution.

But there's a twist; you need bad coffee to make a great empire. Royal resistance to coffee left Germany decaffeinated until after the First World War. "America used to make atrocious coffee and great bombs. But since Starbucks, they've been unable to win a war." Maybe he's on to something here. After all, one German theorist argues that "in sociology, no one really knows what wags what." I do wonder, though, quite how the Romans, Mongols, Aztecs, Incas managed without an espresso, and how Socrates and the Stoics managed all that rational thought while decaffeinated.

The problem may not be with the theory, but with the author's state of mind. This is a funny book that takes some funny routes. It goes off on tangents, it makes brilliant but unsustainable connections, and sometimes just stops and stares into space. These are not the vices and virtues of the caffeine drinker, but the dope smoker. Stewart Lee Allen turns down a joint in Africa, but I didn't believe him. I just hope, when he gets his head together, that he brings us Marijuana: the tangential force in history.