The sack of Rome by the Visigoths in 410 was a milestone in the collapse of the western Roman Empire. The last western emperor died in 476, and although Germanic and Frankish tribal chiefs who exercised power in this period often sought formal acceptance from Byzantium, they recognized no effective jurisdiction from the East after the early sixth century. Elsewhere, Islam arose in Arabia, came into enduring conflict with the eastern Empire, and spread across north Africa and into Spain.
During this unorganized period, two developments were significant for political thought. One was the growth
Of monasticism, especially in communities following the Rule of Benedict of Nursia (c. 480-550), communities which were sometimes inspiring examples of organization and endurance. The monastic program of seeking God through progress in humility also provided some counterweight to other values driving political life in medieval society.
A second development was the assertion of ecclesiastical independence from, or indeed superiority to, lay rulers. The key term in later debates about papal power, plenitudo potestatis (fullness of power), was used by Pope Leo I, although not with regard to clerical-lay relations. The most influential text was Pope Gelasius I’s rebuke in 494 of a Byzantine emperor for intervening in current doctrinal conflicts:
> There are two (Duo sunt) by which the world is chiefly governed: the sacred authority of bishops and the royal power.... Although you rule over the human race in dignity... you understand that, according to the order of religion, in what concerns the receiving and correct administering of the heavenly sacraments you must be subject rather than in command.
World History
