The Kharijites, the oldest and most turbulent dissenting sect of Islam, the reactionaries who opposed the modification of Muslim customs under Hellenistic influence, had appeared in Maghrab early in the 2nd century of the Hijra after their suppression in Asia, and were still a living force there in the fourth century, when their very name was almost forgotten elsewhere. A small group of the less extreme branch of that sect, the Ibadites, still survives in strict isolation in South Algeria. The Idrisids, a dynasty descended from the house of Hasan the son of ʿAli, founded by Idris who escaped from the attempted extermination of his kinsmen at Madina in 169, ruled an independent state in Farther Maghrab in the fourth century. The Umayyads dethroned by the ʿAbbasids in 132, had a representative who escaped to North Africa, and then crossed to Spain where they founded a Khalifate at Cordova which, in the fourth century, had become a great and flourishing power. Indeed the Maghrab was too remote from the Khalifs of Baghdad ever to be under effective control: one after another punitive expeditions marched across North Africa, the disaffected were defeated, the remnant took refuge in the hills, and in the course of a few years or even months the former condition returned again. Obviously those western lands offered a promising field to the agitator, whether political rebel or sectarian leader, and Ibn Hawshab’s missionaries had evidently struck a promising vein in the Berber tribe of Katama. Amongst those who attached themselves to Ibn Hawshab in Yemen was a certain Abu ʿAbdullah Hasan (or Husayn) b. Ahmad b. Muhammad b. Zakariya, afterwards surnamed ash-Shiʿi, a native of Sana and a zealous Shiʿite who had been inspector of weights and measures in one of the districts attached to Baghdad. He was a man not only of superior education and intelligence, but astute and with as good knowledge of how to deal with men. Before long he became one of Ibn Hawshab’s most trusty companions and, when the news came of the death of the two missionaries who had been sent to Africa, Ibn Hawshab determined to send him as _daʿi_, and provided him with the funds necessary for his enterprise. Later on we find him in Africa assisted by his brother, but we are without information as to whether this brother was sent to join him later or set out with him (Maqrizi ii. 11, Ibn Khallikan i. 465).