Bulgarian culture, promoted in the ninth and tenth centuries through the theological schools of Pliska, Preslav, and Ohrid, was influential not only in the Balkans and Russia, but throughout Europe. The Bulgarian Church’s struggle for autocephaly and the competition between Rome and Constantinople for supremacy over Bulgarian territories created great tensions between these two church centers, tensions that will become one of the reasons for the 1054 schism. Although the subject of the schism has been and is being debated at length by both the Orthodox and the Catholic churches it seemed an important issue to be analyzed at the moment, from the perspective of the Bulgarian Church, because with the Christianization of the Bulgarians, the differences that appeared in the dogma and worship of each are highlighted for the first time in the history of the two Churches.