The Synod of the Oak was a provincial synod, held in Constantinople in July of 403, which condemned and deposed John Chrysostom as Patriarch of Constantinople.
This council, organized by his enemies, deposed John Chrysostom, patriarch of Constantinople and also attacked Heraclides, bishop of Ephesus, whom Chrysostom had elected at Ephesus. It seems to be politically motivated and a conspiracy is to be considered.[1]
It was presided over by Theophilus of Alexandria, Acacius of Beroea, Antiochos of Ptolemais, Severian of Gabala and Cyrinus of Chalcedon. Cyril of Alexandria also participated with his uncle.[1]