The Acacian Schism was short break in communion between the Churches of Constantinople and Rome during the late fifth and early sixth centuries, caused by the publication of the Henoticon, an attempt by Emperor Zeno of the Eastern Roman Empire to force a reconciliation between the Orthodox and the Monophysites after the Fourth Ecumenical Council. The Henoticon was prepared by the Patriarch of Constantinople Acacius at the request of the Emperor in the late fifth century. Acacius’ name was applied to the schism as he became the center piece in the resulting dispute among Zeno, Acacius, and Felix III of Rome.
While the Council of Chalcedon of 451 established the Orthodox position in regard to Monophysitism, and establishing it as a heresy, the issue remained a divisive issue in the Church due to imperial political considerations for many decades. The heresy was popular in Syria and Egypt and grew in other parts of the Eastern Empire where Constantinople was not popular. Patriarch Proterius of Alexandria was murdered in 457 and replaced by a Timothy III Aelurus, a Monophysite who after he died in 477, was replaced by the Orthodox patriarch Timothy III Salofacioius from whom Timothy II had usurped the patriarchal throne in 475. Timothy III then reassumed the patriarchal throne in 477 and after his death in 481 he was succeeded by the Orthodox Bishop John I Talaia, who after he offended Zeno, was replaced in 482, by the Monophystic leaning Peter Mongus. The thrones of Antioch and Jerusalem were also occupied by Monophysites: Peter Gnapheus (Fullo) and Theodosius respectively.
Thus, by the time Emperor Zeno came to the throne in 474, the Patriarchates of Alexandria, Antioch, and Jerusalem were in the hands of hierarchs who were disposed to Monophysitism. While Zeno was a friend of Peter Gnapheus and sympathized with the Monophysites, he came to the throne as a defender of Orthodoxy. His defense of the Orthodox position was also forced by his rival for the throne, Basiliscus, who had made himself the protector of the Monophysites. Confronted with a severely divided empire, Zeno looked for a means to reconcile the parties and unify the Church. Zeno took the side of the Orthodox bishops, but he also wanted to placate his friends in Egypt and Syria.
In his attempt to conciliate the issues Zeno turned to the Patriarch of Constantinople, Acacius, for help. Acacius had supported the Orthodox position and had been accepted by Pope Simplicius of Rome. Also, Acacius and John Talaia were enemies, and Acacius had favored Peter Mongus over Talaia for Patriarch of Alexandria. Thus, in this environment Zeno charged Acacius with drafting a letter of union that became known as Henoticon.
The letter endorsed the decrees of the First and Second Ecumenical Councils held in Nicea and Constantinople respectively and the position followed by the Fathers at the Third Council at Ephesus. The heretics Nestorius and Eutyches were condemned and the twelve Chapters of Cyril of Alexandria were endorsed. The Henoticon stated that Christ is God and man, one, not two. His miracles and Passion are the works of one (but it did not say whether person or nature) and those who caused division or confusion, or introduced a phantasy, that is affirm an appearance, were condemned, and that one of the Trinity was incarnate. The text of the letter was meant to satisfy everyone. Yet the Henoticon carefully avoided speaking to the nature or person of Christ, ignoring the Orthodox position of one Christ in two natures, and used the expression of Peter Gnapheus that one of the Trinity was incarnate. Further the letter only named the first three councils with honor and did not mention the decrees of Chalcedon, as a concession to Monophysitism.
The Henoticon did not accomplish what Zeno had hoped. Zeno was able to persuade Acacius to accept the Henoticon which was remarkable as Acacius stood firmly for the Orthodox faith during Zeno’s confrontation with Basiliscus, although his dispute with John Talaia and support for Peter Mongus makes his Orthodox leanings appear weaker. The Henoticon offended many by its omissions rather than by its assertions. Some of the Monophysites accepted it, notably Peter Mongus, which thereby secured him the position as Patriarch of Alexandria, while his Orthodox rival, John Talaia, was exiled, having refused to sign it. John went on to appeal his dismissal to Rome. Peter Gnapheus of Antioch also accepted Zeno’s new law. The extreme Monophysites rejected the Henoticon outright. The Church of Rome found the document unacceptable and completely rejected it. Even in the face of these objections Zeno published the Henoticon in 482 and deposed the Orthodox bishops and extreme Monophysites who refused to accept the compromise.
John Talaia’s appeal to Rome added to Rome’s opposition to the Henoticon. Further, John had a falling out with Zeno and, in 483, fled to Rome where he counseled Pope Felix. After Felix was unsuccessful in negotiating with Zeno and Acacius, the Pope convened a local synod, in 484, at which he deposed and excommunicated Acacius.
Acacius in turn removed Felix’s name from his diptychs. After the death of Acacius’ in 489 and Zeno in 491, his successor as emperor, Anastasius I, while initially professing adherence to Orthodoxy, was unable to reach an agreement with Rome in early negotiations. Over the years as Anastasius grew closer to Monophysitism any chance for success faded as well. In 518, Justin I succeeded Anastasius as emperor. Justin was a firm supporter of Orthodoxy, and with Patriarch John of Cappadocia, progress was made in negotiating a reconciliation with Rome. On March 28, 519, a reunion between the churches was achieved that included the striking of the names of Acacius, Anastasius, and Zeno from the diptychs.