Across the centuries, wars have had complex and contradictory effects on democracy, at some moments triggering great expansions of citizens’ rights and suffrage, and at others tipping power away from the people and toward the state. This illuminating book’s core insight is that modern democracy emerged less as a fulfillment of timeless values than as a “bargain” between rulers and the ruled, struck in the shadow of war. Ferejohn and Rosenbluth argue that modern democracy took root because the appeal of nationalism proved sufficiently potent to rally public support for war but not strong enough to let governments ignore the growing demands of the working classes that had formed during the Industrial Revolution. The book begins with fascinating chapters about war and democracy in classical Athens and Rome; later chapters explore the nineteenth century’s grand armies and the emergence of “total war” in the twentieth century, which had profound effects on the expansion of democratic life in the West. The very different pathways traveled by the Soviet Union, Nazi Germany, and imperial Japan reveal the highly contingent and fragile nature of the democratic impulse.