In the ninth century numerous Shia Arabs, who were advocates of the caliphate of the descendants of Ali and Fatima (Muhammad’s daughter), had converted to the Shia faith the powerful Berber tribe of the Ketama (of the Sanhaga group dwelling in Eastern Algeria); and an emissary of the “hidden” Khalif of the Alide family—Obeid-Allah—arrived in North Africa about 890 and preached the Shia faith and the coming of a Madhi or Divine messenger. Having by the aid of the Berbers overthrown the Aghlabite dynasty of Kairwan, this emissary, who was named Abu-AbdAllah, sent for the Mahdi, Obeid-Allah, the descendant of Ali and Fatima. Obeid-Allah came and founded the great Fatimite dynasty which played such a part in Tunisia, Sicily and Egypt; but ungratefully enough he caused Abu-AbdAllah to be slain and the Ketama tribe to be massacred. He then moved his capital from Kairwan to Mahdia, or Mehdia, on the coast of Tunisia, a city which he founded on the ruins of a Roman town. His son and successor, who nicknamed himself “The sustainer of God’s orders” (Al-Kaïm bi Amr Allah), instituted the practice of never appearing in the open in public without a sunshade being held over his head—the Royal Umbrella which still figures in Moroccan court ceremonial. Under the third sovereign, Al Mu’izz, the dynasty of Fatimite Caliphs reigned over all North Africa, from Morocco to Egypt, and thence to Damascus. The Fatimite general commanding the army in Egypt, Jauhar-al-Kaid, founded the citadel and town of Cairo (Al Kahirah) in 969-71[35], more or less on the sites of the previous Arab capitals of Al-Masr, Al-’Askar, and Al-Katai; and here the Fatimite Caliph transferred his capital and his presence from Kairwan, giving up the rule over Tripoli, Tunis, Algeria and Morocco to Berber viceroys. From the 7th to the middle of the 11th century, the Arab element in North Africa was small and represented chiefly by a few thousand warriors, statesmen and religious teachers, who had in a marvellous manner, difficult to explain, forced their religion, and to some extent their language and rule, on several millions of Berbers, on some 300,000 Christians of Roman, Greek and Gothic origin, and 100,000 Jews. But in the 11th century took place those Arab invasions of North Africa which have been the main source of the Arab element in the northern part of the continent, and without which Muhammadanism might in time have faded away; and a series of independent Berber states have been formed once more under Christian rule.