When I was studying at Columbia University Law School, I read Henri Pirenne’s classic study, Mohammed and Charlemagne (it was an eye-opener and contributed to my studying history in graduate school). Henri Pirenne (1862-1935) was the famous professor of medieval history at the University of Ghent (1886-1930). His analysis showed that the expansion of Islam across North Africa and into Spain transformed the Mediterranean Sea from the great highway to an embattled barrier. Thus, the continuities of Roman culture and prosperity under the Germanic settlers were undermined by the ending of sea-trade. The axis of economic power shifted from southern France to the north (which also became the entry for goods from Byzantium via the Russian rivers and the Baltic Sea). The economy shifted from trade to self-sufficient manorialism, with the advantage to northern France. The family which emerged to leadership was the Carolingians from Herstal in Belgium; Pepin replaced the earlier Frankish royal family. Pepin’s father, Charles Martel, as mayor of the palace, defeated the Saracens at the battle of Tours (732 AD).
The Italian historian, Giusto Traina, has contributed 428AD: An Ordinary Year at the End of the Roman Empire (Translated by Allan Cameron) (Princeton, NJ, Princeton University Press, 2009). It describes the Roman world in the status before the rise of the Carolingians in the Eighth Century. Traina selected 428AD because it marked the end of the independent kingdom of Armenia between Rome and the Persian Sassanids. Traina’s date is near 410AD when Visigoths sacked Rome leading St. Augustine of Hippo to write the City of God, or 476AD when the last Western Roman Emperor retired.
428AD marked the appointment of Nestorius of Antioch as Patriarch of Constantinople. The Byzantine emperor hoped someone from Antioch would keep Antioch happy. Antioch had been the capital of the Seleucid empire which succeeded Alexander the Great, ruling over the former Persian empire as far as the Indus River. Antioch, like Alexandria and Constantinople, was a port and thus supportable by the dominance of the Roman fleet (likewise, as a port on the Adriatic Sea, Ravenna, became the capital of the Western Roman Empire in place of landlocked Milan). Antioch was the place in which the disciples of Jesus were first called Christians, and where St. Peter was the first bishop.
New Persian empires of the Parthians and Sassanids re-conquered the lands east from the Tigris River. At this time, the Sassanids (who were Zoroastrians) encouraged the formation in their empire of the Syriac liturgical tradition using the language of Jesus: Aramaic, as well as of an autonomous Christian Church of the East. The Church of the East adopted doctrines at odds with the Council of Ephesus (431AD) which deposed and exiled Nestorius.
Constantinople, founded a century earlier, was a focus of political intrigue since the emperor held all the power. Over time the Roman emperor adopted the aspects of Oriental Despotisms, such as Persia. The imperial family lived in seclusion in a palace supervised by eunuchs of oriental origin (“which the court received as gifts from foreign nobles or purchased in the slave markets beyond the frontier (the Christian empire prohibited castration of its citizens)”). “A skillful use of propaganda had enhanced the emperor’s charisma, and raised him higher than his immediate predecessors. … All these factors contributed towards a powerful exaltation of imperial autocracy, played out through rituals and ceremonies, and consolidated by imperial privileges.”
Germanic tribes settled in various Western Roman provinces. The Burgundians in eastern Gaul, the Visigoths in Aquitaine (and later in Spain), etc. The Western Church Father Salvian of Marseilles discussed the Germanic settlement in his On the Government of God (De gubernatione Dei). Salvian described “the rapaciousness of imperial taxation and the tyranny of local notables. The latter were considered to be on a par with brigands, as they were responsible for collecting taxes, a practice that barbarians were unaware of.”
The Germanic tribes had been converted by Arian Christians before settling inside the Roman Empire. Until they converted to Catholicism, there was a religious division between the Romanized natives and the German tribes. North Africa was a major granary for the Western Roman Empire. But it was divided among the Catholics of the Roman cities and the Donatists among the rural, native Berber population. During the Great Persecution by Diocletian (emperor 284-305), among the large number of martyrs in the cities, some Christian leaders turned over scriptural books and were spared. The rural people wished those Christian leaders demoted, and when they were not, they formed the Donatist church. St. Augustine in North Africa wrote extensively against Donatism. He also was surrounded by the major political rivalries between the Roman officials in Africa and those in Ravenna. Traina details these developments, as well as those in Roman Egypt, the granary for Constantinople. Monasticism had originated in Egypt among those who had fled to the desert to avoid Roman taxation.
Taina concludes with a chapter on the Shahanshah (King of Kings) who ruled the Sassanid empire between the Euphrates and the Indus rivers. The Sassanid empire included the cities of Samarkand and Bukhara bordering the Oxus River which were posts on the Silk Road across Central Asia to China. Zoroastrian Persia bordered on Buddhist South Asia and was a transmission of the Christian Church of the East along the Silk Road. “Nestorius could not have imagined when he took office in Constantinople that, a few years later, followers of his interpretation of Christianity would be forced to abandon the territories of the Roman Empire and seek refuge in the Sassanian Empire, and that from there they would spread as far as Mongolia, China, and Indonesia.” Marco Polo in the Thirteenth Century encountered Nestorians in China as he traveled the Silk Road under the safe-conduct of the Mongolian Peace.