The importance of the church councils of the 5th and 6th centuries can not be overstated. They give important insights into the late Roman Empire and the role of the church at that time. The Council of Chalcedon (AD 451) is the most outstanding event of its time due to its rich source, dramatic nature and historical significance. The decisions of the Council led in the Greek Church to heavy upheavals, which continue to this day. Hagit Amirav examines for the first time the social dynamics and the different roles of the actors, the power plays of the imperial deputies and the bishops, their gestures and rhetoric, which should serve the consensus finding. At the center of the analysis is Markian in his dual role as Eastern Roman Emperor and as the central figure of the Greek Church.