Arab armies took Gaza in the 7th century. The city passed from the Christian Byzantine Empire into the growing Islamic world. Britannica’s treatment of Roman Palestine and the Arab conquest describes this change of rule.
Gaza became a provincial city under several caliphates. These included the Rashidun, Umayyad, Abbasid, and later Fatimid states. A caliphate was a large political and religious state led by a caliph. It was not a local government based in Gaza. Britannica’s overview of the caliphate explains how these systems worked and where their centers moved.
Arabic and Islam became more central to public life over these centuries. That long change helped shape the language, faith, and society of the region. Palestinian Arab identity later grew from this setting. It did not appear all at once in the 7th century, and a modern national identity cannot simply be placed in that earlier world.
Muslim rule changed Gaza without erasing its Jewish and Christian past. Those communities and their ties to the land remained part of the history. Government, language, and public faith changed around them. The surviving record describes Gaza as a city within several empires. It does not describe the capital of an independent Gaza state.