Church and state in medieval Europe

Church and state in medieval Europe includes the relationship between the Christian church and the various monarchies and other states in Europe, between the end of Roman authority in the West in the fifth century and the beginnings of the Reformation in the early sixteenth century. The relationship between the Church and the feudal states during the medieval period went through a number of developments. The struggles for power between kings and popes shaped the western world.

The Church gradually became a defining institution of the Roman Empire.Emperor Constantine issued the Edict of Milan in 313 proclaiming toleration for the Christian religion, and convoked the First Council of Nicaea in 325 whose Nicene Creed included belief in "one holy catholic and apostolic Church". Emperor Theodosius I made Nicene Christianity the state church of the Roman Empire with the Edict of Thessalonica of 380.

After the fall of the Roman Empire in the 5th century, there emerged no single powerful hoe secular governments in the West, but there was a central ecclesiastical power in Rome, the Catholic Church. In this power vacuum, the Church rose to become the dominant power in the West. The Church started expanded in the beginning 10th century, and as secular kingdoms gained power at the same time, there naturally arose the conditions for a power struggle between Church and Kingdom over ultimate authority.

In essence, the earliest vision of Christendom was a vision of a Christian theocracy, a government founded upon and upholding Christian values, whose institutions are spread through and over with Christian doctrine. In this period, members of the Christian clergy wield political authority. The specific relationship between the political leaders and the clergy varied but, in theory, the national and political divisions were at times subsumed under the leadership of the Catholic Church as an institution. This model of church-state relations was accepted by various Church leaders and political leaders in European history.

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