The city remained largely Christian until the Crusades, its bishop maintaining close ties to the Byzantine Empire.
Caesarea Maritima was the capital of Roman Iudaea province and after the Bar Kokhba revolt it was the metropolis of the diocese of Palaestina Prima.
Following the conquest of the Holy Land by the Islamic armies in the 630s, the diocese and city suffered tremendously and steadily declined in size and importance.
Nonetheless, it remained overwhelmingly Christian, and in the absence of imperial oversight, its independence increased and the archbishop became the effective ruler of the area.
[citation needed] By the 9th century there was a substantial colony of Frankish settlers established by Emperor Charlemagne to facilitate Christian pilgrimages.
Jerome's "De Viris Illustribus" (75) says that Pamphilus "transcribed the greater part of the works of Origen of Alexandria with his own hand," and that "these are still preserved in the library of Cæsarea."