Persia

   The Persia known to Byzantium (q.v.) was created in 226 when the Sassanians (q.v.) overthrew the Parthians. This new and highly nationalistic state made Zoroastrianism (q.v.) the state religion and revived the imperialistic aspirations of ancient Persia. This resulted in centuries of intermittent struggle with Byzantium. However, interaction with Persia went beyond warfare. Active diplomatic relations acquainted Byzantium with Persian court ceremonial, which was adopted in the Byzantine court. Herakleios (q.v.), after defeating Persia, expropriated the title of the Persian king, basileus (q.v.), making it the chief title of the Byzantine emperor (q.v.). Until Justinian I (q.v.) developed domestic silk production, the Persians acted as intermediaries in the silk trade. Manichaeanism (q.v.), which the Persians persecuted, had an impact on Byzantium, notably on Augustine (q.v.). Nestorians (q.v.), persecuted in Byzantium, found refuge in Persia. Nevertheless, it is the centuries of intermittent warfare, chiefly in Mesopotamia, that characterized Byzantine-Persian relations (e.g., in the sixth century Byzantium was at war with Persia from 505-507, 527-532, 540-545, and 572591). The Persians even sacked Antioch in 540, but it was in the early seventh century that Persian armies made extraordinary advances. From 609-619 they conquered Syria, Palestine, and Egypt (qq.v.). The long counteroffensive from 622-628 by Herakleios (q.v.), among the greatest military exploits in Byzantine history, culminated in the utter defeat of Persia. In 631 the True Cross (q.v.) was restored to Jerusalem (q.v.) with great celebration. This final victory in Persia marked the utter triumph of Byzantium after centuries of intermittent warfare with Persia. It also came a year before the death of Muhammad the Prophet. Soon after Muhammad's death in 632 Persia was attacked by the Arabs (q.v.); by the middle of the seventh century the Arab conquest of Persia was complete. In effect, the Byzantine defeat of Persia only paved the way for Arab expansion.