Fatimid Caliphate
The secret network

While the awaited mahdī Muhammad ibn Isma'il remained hidden, however, he would need to be represented by agents, who would gather the faithful, spread the word (daʿwa, "invitation, calling"), and prepare his return. The head of this secret network was the living proof of the imam's existence, or "seal" (ḥujja). It is this role that the ancestors of the Fatimids are first documented. The first known ḥujja was a certain Abdallah al-Akbar ("Abdallah the Elder"), a wealthy merchant from Khuzestan, who established himself at the small town of Salamiya on the western edge of the Syrian Desert. Salamiya became the centre of the Isma'ili daʿwa, with Abdallah al-Akbar being succeeded by his son and grandson as the secret "grand masters" of the movement.

In the last third of the ninth century, the Isma'ili daʿwa spread widely, profiting from the collapse of Abbasid power in the Anarchy at Samarra and the subsequent Zanj Revolt, as well as from dissatisfaction among Twelver adherents with the political quietism of their leadership and the recent disappearance of the twelfth imam. Missionaries (dā'ī s) such as Hamdan Qarmat and Ibn Hawshab spread the network of agents to the area round Kufa in the late 870s, and from there to Yemen (882) and thence India (884), Bahrayn (899), Persia, and the Maghreb (893).
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