For those who accept it (Eastern Orthodox, Roman Catholics, most liturgical Protestants), it is the Fourth Ecumenical Council (calling the Second Council of Ephesus, which was rejected by this council, the "Robber Synod" or "Robber Council").
The Second Council of Ephesus upheld the view of Eutyches, but was overturned two years later by the Council of Chalcedon, called by Emperor Marcian.
Second Vatican Council | World Boxing Council | United States National Research Council | National Research Council | Privy Council of the United Kingdom | British Council | Council of Trent | Council of Europe | National Security Council | Legislative Council | Privy Council of England | Greater London Council | Council on Foreign Relations | Lord President of the Council | United States National Security Council | Legislative Council of Hong Kong | City Council | World Council of Churches | Council of Constance | United Nations Security Council | New York City Council | London County Council | Auckland Council | Her Majesty's Most Honourable Privy Council | United Nations Security Council resolution | Medical Research Council (UK) | Council of Chalcedon | Order in Council | Council of Ministers | Supreme Council of Antiquities |