This book examines the role of marriage in the formation, maintenance, and disintegration of a premodern European diplomatic society. The argument develops in dialogue with the so-called English school of international relations theory, with its emphasis on the contemporary international system as a society of states sharing certain values, norms, and common interests rather than as an anarchy driven solely by power struggles. In studying the place of marriage diplomacy in questions of monarchical and national sovereignty, the book draws on interdisciplinary methodologies that have long characterized academic studies of queenship and, more recently, European diplomatic culture. It begins with Virgil, whose epic tells the story of Aeneas's marriage to Lavinia—the paradigmatic interdynastic marriage. It also considers the inseparability of marriage diplomacy from literary production. Finally, it discusses the factors that precipitated the disintegration of marriage diplomacy, including new technologies of print and the large public theaters for promoting diplomatic literacy.