This doctrine was a cornerstone of Shi'ism, without which one could not be a Shi'a. Among the Sunnis, they also believed in it, but not with the same intensity as the Shi'a. All the hadiths were fabricated to support the awaited Mahdi. What testifies to Bukhari and Muslim is that these hadiths were not transmitted to them. If they leaked into other books whose authenticity was not established, such as those fabricated to flatter the Abbasid state, that the Mahdi would emerge with his companions from Khurasan carrying black banners. This applies to the Abbasids and no one else. And in every era, a Mahdi appears, and new hadiths emerge that apply to these rebels. Ibn Hajar suppressed the hadiths narrated about the Mahdi and found them to be around fifty, stating that their authenticity was not proven to him.

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Just as the idea of the Mahdi and Shi'ism played a role in the West, it played a similar or even greater role in the East. Every now and then, we see a great revolution that lasted for years, such as the Zanj rebellion in Iraq. It arose from the injustice of the rulers and the longing for justice. This revolution appeared at the hands of slaves in Basra, who were originally from the negroes of Africa. They were