This council is not regarded as ecumenical by all Orthodox Christians, but some major voices in the Orthodox world do so, including 20th century theologians Fr. [[John S. Romanides]] and Fr. [[George Metallinos]] (both of whom refer repeatedly to the "Eighth and [[Ninth Ecumenical Council]]s"), as well as Fr. [[John Meyendorff]], Fr. [[George Dragas]] and Metropolitan [[Hierotheos (Vlachos) of Nafpaktos]].
Further, the [[Encyclical of the Eastern Patriarchs]] refers explicitly to the "Eighth Ecumenical Council" regarding the synod of 879-880 and was signed by the [[patriarch]]s of [[Church of Constantinople|Constantinople]], [[Church of Jerusalem|Jerusalem]], [[Church of Antioch|Antioch]], and [[Church of Alexandria|Alexandria]] as well as the [[Holy Synod]]s of the first three.
Those who regard these councils as ecumenical often characterize the limitation of Ecumenical Councils to only seven to be the result of Jesuit influence in Russia, part of the so-called "[[Western Captivity of Orthodoxy]]."