the Roman Empire divided into two, Cappadocia fell under the eastern region.
In the early 7th century there were severe wars between the Sassanid and
Byzantine armies, and for 6 or 7 years the Sassanids held the area. In
638 Caliph Ömer ended the domination of the Sassanids, and the Arab
Ommiades began to attack.
The long lasting religious debates among sects reached a peak with the
adoption of the Iconoclastic view by Leon III, who was influenced by Islamic
traditions. Christian priests and monks who were in favour of icons began
to take refuge in Cappadocia. The Iconoclastic period lasted over a century
(726-843). During this time, although several Cappadocian churches were
under the influence of Iconoclasm, the people who were in favour of icons
were able to continue to worship comfortably.