Do you remember the International Year of the Potato? In 2008, the UN, worried that the vegetable's contribution to food security had been overlooked, decided that the moment had come to show some appreciation. What a time to be alive: before the financial crash had really got going, before the western world was lurching from one political crisis to another, and long before anyone was talking about "lockdown cooking", we felt able to devote a whole year to celebrating spuds. Never such innocence again.
Or so you might think. In fact, according to the historian Rebecca Earle, the potato has played a central role both on our plates and in our politics. If this sounds a bit earnest - well, sometimes, it is. But Earle, a professor at the University of Warwick in England, makes a convincing case. Her wide-ranging, imaginative book joins a growing body of food writing that isn't just concerned with what food is, but with what it means.
And just as potatoes have been turned into everything from vichyssoise to vodka, so their significance has evolved too. Earle traces the potato's journey - courtesy of Spanish raiders in the Andes, where it had been grown for millennia - from a "food that was totally unknown to most of humanity before the 16th century" to one that's found just about everywhere today. But she's most interested in a particular moment, in 18th-century Europe, when the question of what people ate (as opposed to simply whether they ate) became intensely political - and when, as one contemporary writer put it, "newspapers discussed practically nothing but potatoes".
Before then, potatoes had spread through the continent without fanfare. Records are sparse, but Earle, a believer in history told from the roots up, has done plenty of digging. (Of her book's 300-odd pages, 100 are notes and bibliography.) We learn of a Spanish physician who warned that the new vegetables caused flatulence - and, somewhat counter-intuitively, lust. We discover that, in 1624, the feckless Earl of Dorset gorged himself to death on a potato pie, and that The Good Huswife's Jewell (1585) extolled a tart made from "potaton", butter, eggs, spices and "the braynes of three or four cocke-sparrows".
The big change, Earle contends, came in the mid-1700s, when political thinkers began to see the public "the bedrock of the wealth and power of the state". If armies were to be raised, and workers were to be productive, they had to be well-nourished. At the same time, it was thought that the state should keep out of people's lives. The potato resolved this: because it was tasty, people would choose to eat it. Endorsement came from none other than economist Adam Smith, who noted that "the strongest men and the most beautiful women" had potato-heavy diets. And so potato mania spread, with growing contests, eating contests and, in Britain, a "Committee on Potatoes", like something in Gulliver's Travels.
Earle explores its complex afterlives across the British empire, and the ways in which it was absorbed into local cuisine: in India, it eventually became a symbol of nationalist resistance.
In Britain, the Victorians, obsessed with the "deserving poor", started to fear that it was too easy to cultivate, and encouraged inefficiency. Ireland - originally heralded as a nation of "healthy and robust" potato-eaters - was cited as a case in point. After the catastrophic famines of the mid-19th century, the treasury official Charles Trevelyan saw a "glorious opportunity" for Irish people to start paying for food out of their wages, rather than growing it themselves.
Earle has a gift for spotting connections and for explaining how individual habits interact with wider philosophical themes. Still, I wish this one had been more fun to read. The prose can be testing, with its glut of "moreovers", and relentless recourse to the word "statecraft". Discussing colonial tactics, she suggests that the introduction of certain foods had more to do with "legitimising particular forms of governance than with reducing hunger" - which I don't doubt, but is no truer for being repeated three times over a single page.
Still, the most wholesome stuff isn't always the most appetising. For anyone interested in the story behind their food, Feeding the People should be on the menu.