Political

Fourth Council of Constantinople (Eastern Orthodox)

synod convoked by Byzantine Emperor Basil I and held in 879–880, confirming the reinstatement of Photius I, regarded as ecumenical by many members of the Eastern Orthodox Church

The Fourth Council of Constantinople was held in 879–880. It confirmed the reinstatement of Photius I as patriarch of Constantinople.

The result of this council is accepted by the Eastern Orthodox as having the authority of an ecumenical council. In Eastern Orthodoxy, it is sometimes called the eighth ecumenical council.

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