Al-Mansur was unable to pay attention towards Sicily during the revolt of Abu Yazid, where Ibn Ataf was an inefficient governor. Taking advantage of his weakness, the Byzantines stopped the payment of the tribute to the Fatimids. In the meantime, the inhabitants of Sicily also rose against Ibn Ataf, who hid himself in the old castle of Palermo. Confronted by the chaotic situation caused by the rebellious at Palermo and Agrigento in Sicily against the Fatimid amirs, al-Mansur deemed it logical and sensible to entrust Sicily's administration to those whose fidelity was proven beyond doubt, and who, moreover, could maintain a neutral stand, therefore, al-Mansur appointed Hasan bin Ali al-Kalbi as the governor of Sicily in 336/946.
Hasan bin Ali al-Kalbi belonged to an influential Kalbid family, stemming from the tribe of Kalab bin Wabara of Banu Abil Hussain. Under the Aghlabids rule, the Kalabid family began to decline from public notice, but they became the main prop and stay during the Fatimids period, and swiftly found a milieu favourable to their rise, and became a governing element of Muslim Sicily by the middle of the 4th/10th century. Ali bin Ali al-Kalbi, one of the first dynasts of the family and son-in-law of Salim bin Abi Rashid, the then Fatimid governor of Sicily, from 305/917 to 325/936, died at the siege of Agrigento in 326/938. His son Hasan bin Ali al-Kalbi, who had distinguished himself in the campaigns waged by Imam al-Qaim and Imam al-Mansur against Abu Yazid, was the first of a succession of Kalbid governors in Sicily, a kind of hereditary emirate under the Fatimids which lasted until the middle of 5th/11th century.
In Sicily, Hasan bin Ali al-Kalbi finished the internal uprisings and restored peace. He also solidified his army, forcing the Byzantine emperor to resume the payment of the tribute to the Fatimids. On al-Mansur's death in 341/952, Hasan bin Ali returned to Mansuria, leaving behind the government of the island in the hands of his son, Ahmad bin Hasan (342-358/953-969), the second Kalbid governor of Sicily.
The new Fatimid policy led to the origination of the semi-independent dynasty of the Kalbids, which ruled over Sicily for almost a century on behalf of the Fatimids, having considerable autonomy. Hasan, called al-Samsan (431-445/1040-1053) was the last Kalbid governor of Sicily. The Norman Count Roger captured Messina in 1060, and Palermo, the capital of the island fell to them in 1072. The Normans also occupied Syracuse in 1085 and by 1091 the whole of the island came to the possession of the Normans. That was the end of the Muslim rule in Sicily.
The Kalbid era was one of the most prosperous periods in the history of Muslim Sicily. The island developed vital trade and played an important role in the transmission of Islamic culture into Europe. In Sicily, the schools, colleges, mosques and hospitals were also built, the agriculture was promoted and the new industries were set up. It is interesting to note that the medical institution of Palermo was far better than that of Baghdad and Cordova. According to "Encyclopaedia of World Art" (Rome, 1958, 12th vol., p. 459), "The oldest examples of silk weaving are from southern Italy, particularly Sicily, where the first looms were probably put into operation by the Saracens in the 9th century."
The Fatimid art had certainly influenced the Italians through Sicily, and left behind many traces. A number of important pieces of gold and silver works, scattered in south Italy belonged to the Fatimids. The products of this workshop are characterized by a special technique of filigree work arranged in spirals or in vermiculated designs and by simply encased ornamented enamels in Fatimid style. According to "Encyclopaedia of World Art" (Rome, 1958, 12th vol., p. 459), "The influence of Fatimid art is seen in the two lions, each devouring a camel, that entirely cover the mantle of Roger II (1095-1154) almost as if it were half of an enormous orb. The lions are separated by a very stylized palmette. Also Fatimids are the palmettes decorating the edges of the sleeves and the hem of the dalmatic. To this were added the clearly Islamic motif of ornamental scripts - in this case, Naskhi letters, which flow elegantly to form a border."
It may be noted that the magnetic instrument indicating the direction was known as qutb-numa (mariner compass), which came to be used by the navigators of the Mediterranean Sea, from Sicily to Alexandria for the first time. Idrisi (494-548/1100-1154), who compiled his geographical treatise in Sicily, however, is reported to have made an earliest description of the mariner compass. The Egyptians called it samia, because their terms were separate from those of the navigators of the high sea. It is beyond doubt that the Europeans were indebted to the Muslims for the mariner compass, which, they knew most probably after 5th century.