The term “realpolitik” is widely used today as a synonym for “power politics” and understood as the realist approach to foreign policy, a venerable tradition that stretches from Machiavelli and Bismarck to scholar-diplomats of the postwar era such as George Kennan and Henry Kissinger. In this fascinating biography of the concept, Bew reveals its rather surprising intellectual provenance and explains its shifting role in grand debates over statecraft. Bew traces the term to the mid-nineteenth-century writings of a little-known German thinker, August Ludwig von Rochau. For Rochau, “realpolitik” referred less to a philosophy than to a method for working through the contradictions emerging across Europe as the competing forces of liberalism and nationalism gave shape to modern states. A few decades later, the term entered the Anglo-American world, where it became entangled with concepts such as machtpolitik (the politics of force) and weltpolitik (global power politics). In the early twentieth century, the liberal internationalist movement galvanized by U.S. President Woodrow Wilson explicitly cast its ideas in contrast to such concepts. But by recovering the origins of “realpolitik,” Bew suggests that its original meaning might prove useful for today’s internationalists, who, like Rochau before them, are struggling to reconcile liberal ideals with a rising tide of nationalism.