This book examines how Christian writers portrayed the conversion of Slavs beyond the Elbe River—a complex, centuries-long process spanning the tenth through twelfth centuries. Rather than a simple narrative of religious transformation, this conversion unfolded through multiple influences, scholarly debates, and specific historical contexts. The work explores the intricate relationship between conversion and warfare, examining how crusade ideology intersected with territorial conquest. Through detailed analysis, the chapters reveal how this religious and political dynamism affected marginalized populations and demonstrate theology's crucial influence on these processes. The final phase of Slavic integration coincided with a pivotal moment in the development of crusading rhetoric throughout German territories. This timing proved significant for understanding both the conversion process and broader medieval Christian identity. The book offers fresh insights into medieval Christian identity while challenging modern assumptions about paganism. Medieval paganism emerges as a fluid concept rooted in biblical notions of disobedience, rebellion, apostasy, and idolatry—distinct from contemporary pagan movements. These findings will stimulate new research directions on paganism throughout the medieval Latin periphery.