This book focuses on the history of Royal Prussia—the "other Prussia"—which was part of the Polish state from 1454 to 1793. It studies the complex relationship between Germans and Slavs in the Polish-Prussian borderlands, and demonstrates the importance of national and historical myth-making for power politics. Analyzing the rivalry between the multinational, constitutionalist Polish-Lithuanian Commonwealth and its centralized, dynastic neighbor Brandenburg-Prussia, this study contributes to our understanding of the process of early modern nation-building and the formation of national identity.