In 323/935, the Italian pirates raided the coastal regions of the Fatimid, therefore, al-Qaim turned his attention towards Europe, and dispatched a strong squadron of 20 sailing vessels under the command of an Arab Amir al-Bahr (the European, Admiral), Yaqub bin Ishaq al-Tamimi, who made a successful attack on Italy, the south of France, and the coast of Genoa and Calabria, and a part of Lombardy was also brought into subjection. During the Italian raids, the Fatimid forces used mangonels (arradas or dabbabas), an engine missiling the heavy stones on target, which was the then most advanced weapon. Maurice Lombard writes in "The Golden Age of Islam" (Netherlands, 1975, p. 86) that, "Fatimid currency was in use throughout southern Italy. Dinars and particularly quarter dinars (rub) were in circulation and were initiated (tarin), a phenomenon similar to that observed in the Christian kingdoms in northern Spain and the country of Barcelona which, in the eleventh century, initiated the Muslim gold currencies in use in the south of the peninsula."
The Fatimid fleet was unfortunately called back, according to "Islam in Africa" (Lahore, 1964, p. 87) by Prof. Mahmud Brelvi, "just at the moment when Qaim's navy was about to conquer the whole Italy". It was due to the domestic rebellion of Abu Yazid. Syed Zakir Hussain writes in "Tarikh-i Islam" (Delhi, 1935) that, "If Abu Yazid had not staged a massive revolt against the Fatimids, al-Qaim would have probably conquered the whole of Europe, resulting a loss of a great Islamic victory." R. Brunschvig also admitted the loss of Europe in the campaign, vide "Encyclopaedia of Islam" (1934. 4th vol., p. 850). The Fatimid fleet, returning to Mahdiya, also occupied islands of Sardinia, Corsica, Malta, Crete and Cyprus for a short while. And here we cannot but call attention to a fact that the Fatimids were the masters of the entire Mediterranean, and their fleets operated freely throughout its length and breadth.
Al-Qaim had to meet more serious rebellions hatching in the west. The principle revolt took place amongst the Zanata tribe, south of Katama territory, who were the Kharijis under the leadership of Abu Yazid. In 332/943, he marched northwards and took Baghai, Tabassa, Mermajenna and Laribus. The Fatimid forces tried to prevent his advance upon Baja, but were repulsed. Abu Yazid marched towards Kairwan, but this time he suffered defeat. He soon rallied, and took Raqada, and then pressed on to Kairwan and captured it. Mahdiya put up a vigrous resistance for almost a year, repelling Abu Yazid's repeated attempts to storm the capital. Ziri bin Manad, the amir of the tribe of the Sanhaja sent a new reinforcement to the Fatimids, who was a fervent Ismaili. It must be noted that in recognition of his outstanding services, al-Qaim had granted permission to Ziri bin Manad to rebuild and fortify the town of Ashir in the central Maghrib, on the western borders of the Sanhaja territory.
In 334/945, Abu Yazid ordered for massacre and plunder, and captured Tunisia. The Fatimid forces were able to regain the whole Tunisia next year. But, after an interval, Abu Yazid rallied and laid siege to the town of Susa.
We see that al-Qaim was an experienced soldier and an able commander who could lead his forces to victory. Unlike his father, he used to participate in military expeditions. He was bold and courageous, and his activities were not confined to his military operations only. He was not harsh towards his opponents and was tolerant. Prof. Mahmud Brelvi writes in "Islam in Africa" (Lahore, 1964, pp. 86-87) that, "Qaim was a great warrior, and was the first of the Fatimid Caliphs who created a powerful fleet in the Mediterranean. After re-establishing his authority in Mauritania, he turned his attention towards the continent of Europe. His ports had been harassed by the Italian pirates from the Ligurian coast, from Pisa and other places. In reprisal, Qaim overran Southern Italy as far as Gaeta, and his ships of war captured Genoa. A part of Lombardy was also brought into subjection. Unfortunately, the pent-up wrath of the people at the excesses of the savage Berbers, the allies of the Fatimids, burst into a furious flame just at the moment when Qaim's navy was about to conquer the whole Italy. The revolt was headed by a Khariji, named Abu Yazid."
In 325/937, Khalid bin Ishaq, the governor of Sicily laid foundation of a new city, called Khalisa, near Palermo. Its structure and design almost resembled the city of Mahdiya. The chiefs of Sicily and other officials mostly lived in Khalisa, where most of the administration was controlled.
Prof. Masudul Hasan writes in "History of Islam" (Lahore, 1987, 1st vol., p. 492) that, "Al-Qaim ruled for eleven years. He was a man of courage, and did not lose nerves even in the face of great difficulty. He lost most of his territory to Abu Yazid, and was besieged in his capital Mahdiya. In spite of a very difficult situation, he preserved, and out of the civil war which lasted for several years, the Fatimids ultimately emerged victorious. This civil war changed the course of history. But for this civil war, al-Qaim would have occupied a greater part of Italy, and that would have served a base for the conquest of Europe."
Al-Qaim died on 14th Shawal, 334/May 19, 946 at the height of Abu Yazid's rebellion, who at that time had sieged over Susa. His age was 59 years, 6 months and 27 days and the period of the Imamate and Caliphate lasted for 12 years, 6 months and 27 days.