This innovative survey of Byzantium's relations with pre-Christian Bulgaria in the late eighth and early ninth century offers an entirely new framework for understanding the developments that shaped one of the most turbulent periods in the history of the early Medieval Balkans. Unlike previous studies, it integrates the surviving literary sources with the ever-growing archaeological record to construct a comprehensive narrative account of the Byzantine-Bulgar conflict for political mastery in the region. Moreover, the analysis of the changing socio-political structures of Bulgaria provides a basis for understanding its transformation from a loose tribal confederation into a stable monarchy. While this is primarily a regional study, focusing on the territories and peoples controlled by the two competing powers, it is also of interest to students of the Frankish, Arab and steppe-nomad worlds, since the relations between Byzantium and Bulgaria are put into a wider international context.