The political life of every nation is shaped by myths, that is, by stories that express something fundamental about the worldview and values of the people that tell them. This essay focuses on the study of myth in the political life of the United States. It explores a series of theoretical issues as a prolegomenon to the substantive study of American national myths. It offers reasons for studying national myths, distinguishes the study of myth from other categories of academic study, explores the differences between myths and beliefs, examines in depth how myth shapes the non-rational side of political attitudes and action, and gives special attention to methodological issues in the study of the history of political myths as well as ways in which study of the past helps our understanding of political myths in the present and thus allows us to have more influence on reshaping political mythology and political policy in the future.