Americans and International Affairs to 1921 offers an interpretation of US diplomatic history that incorporates recent expansions in the field, focusing on the construction and contestation of US sovereignty and borders by both official and private institutions and individuals. Foregrounding relations with Britain and Native Americans, the book emphasizes changes in law and norms; property rights; the scope of government power; finances and revenue; immigration policy; and the racialized and gendered rhetoric of "civilization." The chronologically organized chapters cover the colonial period through the Articles of Confederation; the Constitution and the French Revolutionary and Napoleonic Wars; the collapse of the Spanish New World empire and related conflicts over the future of slavery; the Civil War and resulting changes to citizenship and the federal government; the development of a federal immigration bureaucracy and formal empire; and a temporally and geographically capacious approach to World War I. The book can stand alone as a survey of the United States in the world to 1921, but it was designed to be used in US diplomatic history courses in which instructors can combine it with material from their own areas of expertise and/or with student research projects. Each chapter contains notes and a bibliography to support the chapter, as well as an additional bibliography of scholarship on topics beyond the scope of the chapter. The book includes a number of original maps, plus a variety of primary source images and essential documents, as well as a guide to online primary source collections.