In the East in the 6th cent., Justinian was ruler of church and state equally, and thereafter the Orthodox Eastern Church in the Byzantine Empire was in confirmed subservience to the state. This domination of state over church is called Erastianism, after the theologian Erastus. When the empire began to disintegrate, the power of the state over the church declined; and under the Ottoman sultans the situation was reversed to the extent that the patriarchs of Constantinople were given political power over the laity of their churches.
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