Here's more strange history about the Abbasid revolt:
The Abbasid revolt originated in the eastern province of Khorasan in the mid-8th century, fueled by widespread discontent with Umayyad rule. The Abbasids, claiming descent from Muhammad's uncle Abbas, capitalized on various grievances, including discrimination against non-Arab Muslims (mawali), heavy taxation, and perceived impiety of Umayyad rulers. Led by Abu Muslim Khorasani, Abu Muslim's army composed largely of Arab settlers disillusioned with Umayyad rule, marched under black banners, forming a powerful force that swept westward in open revolt, defeating Umayyad forces. Abbasid Revolution Now, here we have the contradictory statements that the revolt arose from discrimination against the non-Arab Muzzies, but it was fought by "Arab settlers disillusioned with Umayyad rule". More plausibly, the non-Arab settlers rebelled because they could, and claimed their leaders were related to Mohammad, and therefore the legitimate rulers of the Caliphate, as a cover story. The Shia would then be something like "protestant" Muzzies questioning the established orthodoxy, and shaking up the
status quo. How did Moe's relatives find themselves so far away from Eastern Arabia in Khorasan? That doesn't ring true.