Contours of Conversion: The Geography of Islamization in Syria, 600-1500 | Thomas Carlson - Academia.edu
This lengthier process was also not one-directional. Muslims converted to Christianity as well as vice versa. Ruined non-Muslim religious sites could sometimes be rebuilt.
Al-Muqaddasī (ﬂ. late tenth century) acknowledged that despite his high praise for Syria’s many advantages, “some [of its people] have apostasized.”
Yāqūt al-Ḥamawī (d. 626/1229) mentioned a village named ʿImm between Aleppo and Antioch, “in which today everyone is Christian,” but he quotes the Risāla of Ibn Buṭlān from the eleventh century to say that two centuries earlier it had a mosque.
In certain contexts Islam was not the only religion supported by the state, as Muslim rulers sometimes provided stipends to Jewish and Christian religious authorities in addition to the ulema.
Furthermore, the Byzantine reconquest and the Crusades reintroduced non-Muslim rule to portions of Syria from 358/969 to 690/1291, so that even state support for Islam could not be taken for granted. Indeed, under Frankish rule a large enough number of Muslims sought to become Christian that canon law needed to be developed in order to handle diﬃcult social questions regarding marriage and slavery in such cases.
As Benjamin Kedar concludes, “in the Frankish Levant, passages from Islam to Christianity and vice versa were not rare at all.”