Byzantine naval power and trade: the collapse of the western frontier

Abstract

In the eleventh century A.D., the Byzantine Empire witnessed a number of military and political disasters. One of the most significant of these was the collapse of the western frontier and final loss of southern Italy in 1071. However, the failures of the Byzantine Empire in the West by the eleventh century were simply the end result of much earlier problems. Following the expansion of Islam in the seventh and eighth centuries, Byzantium became more defensive and entrenched in her approach to the rest of the Mediterranean world. This took the form of an increased restriction and regulation of all trade within her borders. The closing of maritime trade routes hurt her own merchants more than anything else and contributed to the rising prosperity of the nominally Byzantine city-states of Italy along the western frontier. The merchants of these cities, as semi-independent Byzantine subjects, began to dominate the lucrative East-West trading networks of the Mediterranean. This was to weaken the Byzantine merchant marine and, as a consequence, the Byzantine navy in the West. Moreover, the Byzantine state's rigid and entrenched position prevented her from adapting to the new ideas of commerce developing in the West and from exploiting fully the emerging commercial revolution of the tenth and eleventh centuries. As a result, Byzantium's inflexibility and antiquated views began to both weaken her military strength and undermine her authority in the West. As other, more dynamic political alternatives emerged in southern Italy by the eleventh century, Byzantium was to find herself increasingly unable to enforce her political and economic will in the West. It was only a matter of time then before Byzantine authority was disregarded and eventually replaced by new powers in the regions of southern Italy.