The Council of Constantinople of 869-70 was highly dramatic, with its trial and condemnation of Patriarch Photius, a towering figure in the Byzantium of his day, and the tussle of wills at the council between the papal legates, the imperial representatives and the bishops. It was church politics and personalities rather than issues of doctrine, such as icon veneration, that dominated the debates. Out of all the acts of the great early councils, the acts of this council, of which this edition is the first modern translation, are the nearest to an accurate and complete record. Its protest against secular interference in ecclesiastical elections was taken up later in the West and led to this council’s being accorded full ecumenical status, although it had been repudiated in Byzantium soon after it was held. No early council expresses so vividly the tension between Rome’s claim to supreme authority and the Byzantine reduction of this to a primacy of honour.