This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book explores the thinking and motives behind Alcuin’s and Hincmar’s recourse to Augustine’s thought in their attempts to legitimate Carolingian rule, consolidate and maintain the empire - and to what extent these authors in fact used it. It is concerned with Augustine and his De civitate Dei, and discusses the political advice of Alcuin and Hincmar. The book examines the themes and concepts of Augustinian thinking that are relevant to an examination of the Carolingian material. It focuses on the two high-flying Carolingian political advisers Alcuin and Hincmar. The book provides a survey work and forms the basis upon which Carolingian political thought and political ethics can then be scrutinised – ideas that, while echoing Augustine in many respects, were arguably derived from propositions and demands fundamentally different to his own.