The field of U.S. foreign relations history is a vibrant one that has evolved and expanded dramatically in recent decades. In fact, the very name of the field has been in flux, which has reflected the field’s upheaval and innovation. Historians of U.S. engagement with the world used to write “diplomatic history,” which typically focused on state-to-state diplomacy and policymaking elites. By 2000, the field became the history of “American foreign relations” broadly defined, which included traditional diplomatic and policy history but was more expansive to encompass any interaction between Americans and people from other countries. Today, many historians—and an increasing number of job ads—dub the field “America and/in the world” or “the U.S. and/in the world,” an umbrella term which embraces diplomatic and foreign relations history, as well as scholarship that situates U.S. history in an international or transnational context.