Council
Chalcedon
451 · Chalcedon
Attested. The definition and the votes are extensively recorded. What the definition meant, and whether it betrayed Cyril, was disputed immediately and still is.
Convened by. Marcian and Pulcheria
Issues. How to say that Christ is fully God and fully human after the crisis of 449, without returning to a split Christ or to a mixed nature.
Outcomes. A definition that Christ is acknowledged in two natures, without confusion, change, division, or separation, and that Leo's Tome agrees with Nicaea. Dioscorus was deposed, mainly for his conduct. Canon 28 renewed Constantinople's ranking, which Roman legates resisted. Many in Egypt and Syria rejected the definition. Churches that do are later called Oriental Orthodox; they are not 'monophysite' in the crude sense older textbooks used.
Canons or creeds. The definition is a doctrinal formula, not a list of biblical books. Canon 28 is jurisdictional and was disputed at the time.