Not another book about the Bright Young Things, surely? All teddy bears called Aloysius and floppy-haired young men going over to Rome for aesthetic reasons? Actually, no it isn't. Lucy Moore's latest book is something far more fresh and interesting: a social history of America in the 1920s. The result is a varied and dazzling portrait gallery of crooks and film stars, boxers and presidents, each brilliantly delineated and coloured in by a historian with a novelist's relish for human foibles.

After the tragedy of the previous decade, in which millions of idealistic young men went to their deaths for nebulous reasons, people in the 1920s were set on having fun. Yet the curious thing about men and women wholly set on fun is that they end up seeming as tragic, or at least as sad, as their predecessors - but a lot less dignified. One 1920s writer described his peers as greedy and discontented, intelligent but uneducated, slack of mind though trim of body. FScott Fitzgerald, the most emblematic figure of the decade, knew full well that his own and others' youthful hedonism was merely “despair turned inside out”. There are contemporary echoes here aplenty, though Moore is scrupulous not to exaggerate them.

In a hugely enjoyable stroll through the portrait gallery, we meet Jack Dempsey, Charles Lindbergh and Fatty Arbuckle. We learn about President Warren Harding, drunk, a womaniser and incompetent, but much loved by the American people for his “simple, well-intentioned affability”. “I have no trouble with my enemies,” he once observed. “But my damned friends, my God-damned friends.” George Osborne, take note.

We eavesdrop on the Algonquin Round Table, with Dorothy Parker making quips such as “Brevity is the soul of lingerie”, in between suicide attempts with razors and pills. “Dorothy, if you don't stop this sort of thing you'll ruin your health,” drawled Robert Benchley. But America contains multitudes, so we also witness the Scopes Monkey Trial in Tennessee, on creationism v evolution. The chasm between these two different worlds (Manhattan and Tennessee), as Moore notes, was unbridgeable. HL Mencken, usually a great journalist, covered the trial in the worst possible way, making friends with the simple-minded believers down there, all fake sincerity and politeness, before returning to civilisation - well, Baltimore - to write up “brutally contemptuous” accounts of their laughably gauche and old-fashioned faith. A trick repeated ad nauseam by every third-rate television-documentary maker today.

Times Archive, 1925: Darwinism in schools

The trial to test the validity of the anti-evolution law in the state of Tennessee began today with prayer

• Archive Topic: The Scopes 'monkey' trial

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The decade's corrosive cynicism shocks even now. Flappers wore “a tiny gold spoon or box containing cocaine” on a necklace, and a popular song went, “My sister sells snow [cocaine] to the snow birds/My father sells bootlegger gin/My grandma does backstreet abortions/ My God! How the money rolls in!” And those prohibition speakeasies weren't nearly so thrillingly and illicitly glamorous as you might imagine. Liquors available included Yack Yack bourbon, made from burnt sugar and iodine, Panther whisky, containing fusel oil, and Jackass brandy, which caused internal bleeding.

One who profited most from all this was Al Capone, who snorted so much coke that his septum was perforated. He is pictured here wearing “gold-piped royal blue silk pyjamas embroidered with his initials”, or “distractedly dipping the tips of his fingers in the silver bowls of roses on his desk”. Moore describes him acidly - as she might many a coke-guzzling modern celebrity - as “neither entertaining nor articulate, but more than willing to be profiled”. He died at 48 of syphilis, contracted in one of his own “whoopee spots”, or brothels.

Moore has a wonderful eye for the telling detail. This was the decade that first saw the use of such phrases as joyride, lounge lizard, and - ominously - loan shark. It was also the decade that saw America's first self-made female millionaire, a black woman called CJ Walker. Her fortune came from selling straighteners for kinky hair. And of all the scenes from history I'd love to have witnessed, what could beat the great blues singer Bessie Smith, one sultry night in North Carolina? She and her band were playing in a tent - black performers were banned from public halls - when the Ku Klux Klan arrived outside. Her male bandsmen were terrified, so Bessie marched out to confront the Klansmen herself. “One hand on her hip, and shaking the other at them,” she unleashed such an astonishing torrent of abuse that the American Knights hitched up their skirts and fled. “I ain't never heard such shit,” said Bessie, returning to the band. “As for you, you ain't nothing but a bunch of sissies.”

Along with all the frivolity, the decade had seen mortage indebtedness more than doubled between 1922 and 1929, and on the eve of the Great Crash, 75% of all cars were bought on hire purchase. “Wealth is the chief aim of man,” said President Calvin Coolidge. But most people were keener on credit, or making easy money on ludicrously overvalued stocks and shares. When things fell apart, Andrew Mellon, the austere secretary of the Treasury, said simply, “People will work harder, live a more moral life. Values will be adjusted.” In 1932, a Republican president was voted out in favour of a Democrat - Roosevelt and his New Deal. Change had come to America. Plus ça change .

Anything Goes by Lucy Moore
Atlantic £19.99 pp304

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