Name of the eastern church after schism of 1054

In the year of 1054 there was an event where there was a separation in the formal institutional which was done between the Byzantine Empire of Eastern Church.

Explanation:

So the social name of the Eastern church after Schism of 1054 is now known as East Orthodox church. From the event there were two churches which was split, in which one was Eastern Christian churches and the Western church.

There was an in charge who was considered as the head of the Eastern Orthodox churches was Patriarch of Constantinople.

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