“An ecumenical council, also called general council, is a meeting of bishops and other church authorities to consider and rule on questions of Christian doctrine, administration, discipline, and other matters in which those entitled to vote are convoked from the whole world (oikoumene) and which secures the approbation of the whole Church.

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The first seven ecumenical councils, recognised by both the eastern and western denominations comprising Chalcedonian Christianity, were convoked by Roman Emperors, who also enforced the decisions of those councils within the state church of the Roman Empire.

Starting with the third ecumenical council, noteworthy schisms led to non-participation by some members of what had previously been considered a single Christian Church. Thus, some parts of Christianity did not attend later councils, or attended but did not accept the results.”

List:

  1. The First Council of Nicaea (325)
  2. The First Council of Constantinople (381)
  3. The Council of Ephesus (431)
  4. The Council of Chalcedon (451)
  5. The Second Council of Constantinople (553)
  6. The Third Council of Constantinople (680–681)
  7. The Second Council of Nicaea (787)