Usman glared a Jihad on the 21st of June 1804 and gave notice of war to the Hausa kings within few years. Meanwhile, before then he had succeeded in replacing most of the Hausa kings with Fulani hegemony. Kebbi, Kano, Katsina, Gobir and Zaria had fallen to the Jihadist at the interval between 1805 and 1809.
However, at about thirty years of the operation, the Fulani hegemony had successfully conquered the whole of the northern part with the exception of Borno and other states that refused to accept Islam.
Thus, Dan Fodio used trickish tactics in that he did attack the Northern Kings one after the other; Had it been he attacked all of them at the same time, he could not have achieved his aim. And for the fact that he did his assignment well, they surrendered and Fodio took possession.
Fodio later built a permanent base at abonge where he received delegations of Fulanis from all over the north in 1805. He equally gave the Jihadist leaders the authority to rid the unbelievers and establish Islam in the whole of Hausa land.
Moreover, the Jihad in Hausa land came to an end in 1808 following the death of Yunfa in a battle outside his capital of Alkalawa. Hence, after dominating the whole of Hausa land by the Jihadists, the foundation of Sokoto Caliphate was laid.