Following the Gothic War (535–554), and until the arrival of the Normans, much of Southern Italy's destiny was linked to the fortunes of the Eastern Empire, even though Byzantine domination was challenged in the 9th century by the Lombards, who annexed the area of Cosenza to their Duchy of Benevento. Consequently, the Lombard and the Byzantine areas became influenced by Eastern monasticism and much of Southern Italy experienced a slow process of orientalisation in religious life (rites, cults and liturgy), which accompanied a spread of Eastern churches and monasteries that preserved and transmitted the Greek and Hellenistic tradition (the Cattolica monastery in Stilo is the most representative of these Byzantine monuments). From then to the Norman conquest of the 11th century, the south of the peninsula was constantly plunged into wars between the Byzantines, Lombardy, and the Islamic Caliphate.