The territories conquered at Byzantium’s expense by the Muslim armies in the seventh century were largely inhabited by Christians. During the three centuries before the arrival of the Muslims, the sacred landscape of the regions overlooking the Mediterranean was radically transformed through a dense construction of Christian architectural complexes. The nature of the seventh-century Islamic conquest affected, but did not obliterate, these late antique constructions. The corpus of churches in use during the early Islamic period was composed of late antique churches and several new constructions.