The Hagia Sophia was to the Eastern Orthodox faithful as Saint Peter's Cathedral in Rome is to the Roman Catholic faithful.
====The Spread of the Eastern Orthodox Faith to Eastern Europe(9th Century)====
Monasticism as well missionary activities began to develop, primarily in Eastern Europe.
In the 9th century, Bulgaria became an Eastern Orthodox nation and neighboring nations began to follow Bulgaria's conversion.[2]
)====Schism with the Roman Catholic Faith(11th Century)====
History tends to place 1054 as the date of the schism between the [[Roman Catholic Church]] and the Eastern Orthodox Church.