In 1804, Shehu Usuman dan Fodio, a Muslim clergyman and reformer from the Fulani pastoralist clan in northern Hausaland (now part of northern Nigeria), led a migration westward away from Degel to Gudu (both in the region of Gobir) in order to escape persecution by a rival Muslim clan, the farming Hausas. The migration, it is clear from the biography of dan Fodio written by his brother Abdullah, was interpreted by the Shehu’s followers (if not by his enemies) as a renunciation of any allegiance between himself and the dynasty of the Hausa "infidels" in Gobir, and a call to military jihad against those same infidels.
In Degel, before their migration, Usuman orchestrated an oath of allegiance to galvanize his followers and motivate them to wage jihad against their enemies. He invoked the memory of the Prophet Muhammad's own migration in 622 ( hijra ) that was preceded by an oath his allies took to wage jihad by his side against their enemies, an oath remembered in Islamic history as Second Aqaba. In following Muhammad's example, dan Fodio utilized the established Islamic practice of taqlid ("imitation") in much the same way the Abbasid rebel al-Bukayr did in the eighth century. Al-Bukayr, too, had deliberately imitated the example of the Second Aqaba oath. Al-Bukayr's purpose in calling up this memory was to motivate Shiites to join the Abbasid revolution against the Umayyads. Taqlid became a central pillar of Abbasid rule, especially after 935.
Dan Fodio's jihad resulted in the overthrow of the Hausas and the establishment of a Fulani caliphate in Sokoto in 1808. His approach is best summed up in a passage from his Ta’alim al-Ikhwan ("Instruction of the Brethren"):
"The designation of people as unbelievers is a question of tradition, whose roots are in the Revealed Law of Islam: according to consensus there is no place in it for free play of the intellect nor any way into it for analogy."
By appealing to "tradition," Usuman made it clear that he intended to appeal to taqlid ("imitation") alone, and, that he disdained all use of ijtihad, or, "free play" of the intellect. That is to say, innovative thought or independent thinking were forbidden. But, he went further by also ruling out any place for qiyyas ("analogical reasoning"). In so doing, Usuman paved the way for appeals to jihad based on revelation and on religious authority.
Source: Mervyn Hiskett, The Sword of Truth: The Life and Times of the Shehu Usuman dan Fodio (Evanston, IL: Northwestern University Press, 1973)
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