control over North Africa, and laying the foundations for Cairo. The first phase of Muslim rule began with the conquests of the third Aghlabid Emir Ziyadat Allah I of Ifriqiya, and consolidated with the reign of the ninth Emir Ibrahim II of Ifriqiya after the conquest of Taormina. The first attempt to capture Syracuse was under general Asad ibn al-Furat, although it ended in a Byzantine victory. A strong combination of Ifriqiyan, Persian and Andalusian troops helped to capture the Island between 830 and 831. After a revolt was suppressed, the Fatimid Caliph Al-Mansur Billah appointed a member of the Kalbid dynasty, Al-Hasan ibn Ali al-Kalbi, as First Emir of Sicily. The Kalbids ruled Sicily from 948 to 1053. Al-Mu'izz ibn Badis, fourth ruler of the Zirid Sanhaja dynasty in North Africa, attempted to annex the island for the Zirids, but his attempts failed. The new Arab rulers initiated revolutionary land reforms, which in turn increased productivity and encouraged the growth of smallholdings, a dent to the dominance of the landed estates. The Arabs further improved irrigation systems through Qanats, introducing oranges, lemons, pistachio, and sugarcane to Sicily. Ibn Hawqal, a Baghdadi merchant who visited Sicily in 950, commented that a walled suburb called the Kasr (the palace) was the center of Palermo, with the great Friday mosque on the site of the later Roman Catholic cathedral. The suburb of Al-Khalisa (Kalsa) contained the Sultan's palace, baths, a mosque, government offices, and a private prison. Ibn Hawqual reckoned there were 7,000 individual butchers trading in 150 shops. By 1050, Palermo had a population of 350,000, making it one of the largest cities in Europe, behind Moorish-Spain's capital Córdoba and the Byzantine capital of Constantinople, which had populations over 450–500,000. Palermo's population dropped to 150,000 under Norman rule. By 1330 Palermo's population had declined to 51,000, possibly due to the inhabitants of the region being deported to other regions of Norman Sicily, or to the Norman County of Apulia and Calabria. The local population conquered by the Muslims were Greek-speaking Byzantine Christians, but there were also a significant number of Jews. Christians and Jews were tolerated in Muslim Sicily as dhimmis, and had to pay the Jizya poll tax, and Kharaj land tax, but were exempt from the Zakat alms-giving tax Muslims had to pay. Many Jews immigrated to Sicily during Muslim rule, but left after the Normans arrived. In the