Constantinople and Rome in the 9th Century. The Schism Development and Its Representation in Correspondence of Patriarch Photius and Pope Nicholas I
Based on an analysis of the correspondence between Photius, Patriarch of Constantinople, and Pope Nicholas I, the article focuses on reconstruction of the reasons of conflicts between Rome and Constantinople in the 9th century. Historiography on this issue is quite extensive, but there are some gaps regarding the correspondence of Photius and Nicholas, which reflect an important stage in the development of schism between the two churches in the 9th century. The study of this correspondence has identified political, canonical and dogmatic reasons for the conflict, which represent a significant stage in the schism history.