The city now known as Palermo has been renamed by every conqueror, and it has had many. Founded c. 730 BC by the Phoenicians as Zis, it became a possession of Carthage, then Rome, then Vandals, then Ostrogoths, and then Byzantium. When the Muslims took the island in 904 AD after fierce fighting, the Arabs renamed the town Balarm, and made it the capital of the Emirate of Sicily. Over the course of the next decades, Balarm blossomed, until – it was said – it could compete with Cordoba and Cairo in influence and splendor. Under the rule of the Fatimid caliphs, the flourishing port became a center of trade (mostly agricultural … the Muslims introduced oranges, lemons, pistachios, and sugarcane) and culture. But after dynastic quarrels among the Muslims, Sicily was overrun by Christian mercenaries, including the Norman Robert Guiscard, in 1072.