The Henoticon (“act of union”) was a document issued by the Eastern Roman Emperor Zeno in 482 in an attempt to reconcile the differences between the Chalcedon and non-Chalcedon supporters in the aftermath of the Fourth Ecumenical Council. The document was prepared by Acacius, Patriarch of Constantinople. By this act Zeno hoped to placate the populous of the Roman provinces of Egypt, Palestine, and Syria that were increasingly adopting the formula of Monophysitism that was condemned by the Council.
With the repose of Leo I, Zeno succeeded as the Emperor of the Eastern Roman Empire, but was forced by the usurper Basiliscus to leave the throne in 475. Basiliscus had the backing the non-Chalcedonian party in Alexandria. After Zeno’s return to the throne a year later the non-Chalcedonian party remained prominent in Egypt.
In 482, the leadership of the Church of Alexandria passed to Peter Mongus (Peter III), who was a Miaphysite among the non-Chalcedonians. In view of the continuing controversy between the Chalcedonians and non-Chalcedonians, Acacius prepared a document, the Henoticon, for Emperor Zeno that was intended to provide a basis for uniting the two sides. Zeno promulgated the Henoticon without the approval of any Synod of bishops. By this act, Zeno hoped to placate the increasingly non-Chalcedonian provinces of Egypt, Palestine, and Syria.
The items that the Henoticon endorsed included:
- the faith defined at the First and Second Ecumenical Councils;
- the condemnations of Eutyches and Nestorius that had been issued at Chalcedon;
- an explicit approval of the twelve anathemas of Cyril of Alexandria; and
- avoidance of any statement whether Christ had one or two natures, in an attempt to appease both non-Chalcedonian and Chalcedonian Christians.
The document failed to satisfy either side. All church leaders took offense at the emperor's open dictate of church policy. After two years of prevarication and temporializing by Acacius, the Pope of Rome, Felix III, in 484, condemned the document and excommunicated Acacius. Acacius in turn removed the name of Pope Felix from the diptychs, effectively beginning the Acacian Schism. The excommunication was largely ignored in Constantinople, even after the death of Acacius in 489.
Zeno died in 491. His successor Anastasius I, as emperor, was sympathetic to the non-Chalcedonians, but he accepted the Henoticon. However, Anastasius was unpopular because of his Miaphysite beliefs, and Vitalian, a Chalcedonian general, attempted to overthrow him in 514, but failed. Anastasius attempted to heal the schism with Pope Hormisdas of Rome, but this failed when Anastasius refused to recognize the excommunication of the now deceased Acacius. General Vitalian tried to overthrow the emperor for a second time, but he was defeated by loyal officers.
The schism caused by the Henoticon was officially settled in 519 when Emperor Justin I recognized the excommunication of Acacius and reunited the churches of Rome and Constantinople. However, the Patriarchates of Alexandria, Antioch, and Jerusalem split, forming both non-Chalcedonian and Chalcedonian sees.