The hilarity of the Abbasids' (the Islamic Caliphate's) position in the Ages system is too much to bear.
Camels
Why the fuck are Camels a resource in this game? Are they going to make terrain extra relevant in combat? Is this Imperator: Rome?
Ibn Battuta
Ibn Battuta was never a ruler. He wasn't even born in the Abbasid Caliphate; rather, he was born in Tangier, in one of the various breakaway sultanates in present-day Morocco. By the time he was born, the Mongols had already destroyed the Abbasid Caliphate, and the Mamluks (slaves) of Egypt had made its dynasty their family of religious leaders. Ibn Battuta travelled almost five times more than Marco Polo, if his self-published exploits are true. The historicity (evidence) of his work is a bit scant, however; for example, evidence that he really did travel to Syria wasn't discovered until 2010.
Ibn Battuta has an "Endeavor" in Civ 7 that lets him steal the Maps of other factions over time, gradually undoing the Fog of War in their lands. I don't know what to make of this. His units have +1 to their vision range.
Predecessors
Persia being a predecessor for the Abbasids is hilarious. The first Muslims destroyed Persia. Before learning the entire roster, I hoped that we wouldn't have any Civs who genocided their prior-Age versions; clearly I was short-sighted in this reading. One could point out that the Abbasids started in Persia when they were building up their power base to eventually replace the previous Caliphate (the Umayyads); sure, but the Abbasids and their supporters weren't Persians. They considered themselves Arabs.
Egypt being the other predecessor for the Abbasids is similarly hilarious, but a bit more excusable. This is because the Abbasids in Civ 7 appear to be based on the Mamluk (battle-slave) Sultanate of Egypt, for reasons I detailed above. At the time of the Mongols, Egypt was the strongest Islamic power that the surviving Abbasid nobles were accepted in, so they essentially became the country's dynasty of high priests. Imagine the Pope, but with no authority outside of a single nation. That was the Abbasids after the Mongols. Before this sorry arrangement for the "Caliphate" at this point, the Abbasid power base was Iraq.
Successors
Buganda was never,
ever an Abbasid dominion. It's also Catholic right now, but that's neither here nor there. It was essentially irrelevant until the 1860's (for the Arabs) and the 1870's (for the British and French).
The Mughals being Abbasid successors is an amusing notion. I mean sure, both were Islamic. The Mughals come more from THE MONGOLS, however; after the Timurids' LARP as a Horde was petering out, some went east into India and some stayed as the new Persia. They really should have just had Persia again; but oh well, I guess they can't have "bad" states in this game.