There are two surprises in Andrew Ross Sorkin’s 1929: Inside the Greatest Crash in Wall Street History—and How It Shattered a Nation. One is immediately obvious: his book has appeared a full four years before the centennial, posing a challenge for the publicity team. The other may be apparent only to its close readers. For the story Sorkin tells in 1929 implicitly undermines the conventional wisdom, which he explicitly endorses, about what his subtitle calls “the Greatest Crash in Wall Street History.”

Though the percentage decline in stock prices on October 29, 1929 has been surpassed since—on October 19, 1987 and March 16, 2020—neither swoon was followed by anything like the decade-long Great Depression that “Black Tuesday” is supposed to have made inevitable. Yet the conventional wisdom persists. It was propagated by the highly publicized Pecora hearings (named for the investigation’s fourth and final chief counsel, Ferdinand Pecora) in the early 1930s and by President Franklin Roosevelt’s inaugural speech in 1933, by the admiring New Deal histories of the 1950s and ’60s, and perhaps most effectively by the witty economist John Kenneth Galbraith’s The Great Crash 1929, published in 1955 and never out of print. In this view, the 1920s were a drunken party, full of frivolity and chicanery, followed by the extended—and