Foreword; Preface; Part I. History: 1. Political parties, religious problems and opening conflict; 2. Ignatius' resignation and Photius' canonical election; 3. The Synod of 861; 4. Nicholas, Photius and Boris; 5. Photius' downfall and the council of 869-70; 6. Photius' rehabilitation and the Synod of 879-80; 7. The second schism of Photius, a historical mystification; 8. Photius, Leo VI and the healing of the extremists' schism; Part II. Legend: 1. The Photian case in latin literature till the twelfth century; 2. Oecumenicity of the eighth council in medieval western tradition; 3. Western tradition from the twelfth century to the fifteenth century; 4. Fifteenth century till the modern period; 5. Photius and the eighth council in the eastern tradition till the twelfth century; 6. From the thirteenth century to the modern period; Conclusion; Appendices; Sources; Bibliography; Index.