From the conflicts that presaged the First World War to the aftershocks of the Cold War, the twentieth century was by far the bloodiest in all human history. How can we explain the astonishing scale and intensity of its violence when, thanks to the advances of science and economics, most people were better off than ever before? Why did progress descend into genocide? In his most important book to date, Niall Ferguson resolves the paradox of the Age of Hatred. With all his trademark brilliance, vigour and originality, he sets out to explain what went wrong with modernity. It's a quest that takes him from the Siberian steppe to the plains of Poland, from the streets of Sarajevo to the beaches of Okinawa, and from the graveyards of Guatemala to the killing fields of Cambodia. The answers he finds are novel and compelling. Drawing on a pioneering combination of history, economics and evolutionary theory, The War of the World is a revolutionary reinterpretation of the modern era.