Abbasid Revolution: Abu Muslim Khorasani begins an open revolt against Umayyad rule, which is carried out under the sign of the Black Standard.
The Black Banner or Black Standard (Arabic: , romanized: ar-ryat as-sawd, also known as (ryat al-'uqb, "banner of the eagle" or simply as , ar-ryah, "the banner") is one of the flags flown by Muhammad in Muslim tradition. It was historically used by Abu Muslim in his uprising leading to the Abbasid Revolution in 747 and is also associated with the Abbasid Caliphate. It is also a symbol and is associated with the Islamic eschatology (heralding the advent of the Mahdi). The Black Banner, which is different from the flag used by IS, has been used by some jihadist and other militant groups since the 1990s, including some Chechen groups. Scholars have interpreted IS's use of a similar black flag as representing their claim to re-establishing a Caliphate. Similar black flags have been used throughout Islamic history, including in Afghanistan during the early 20th century.
The Abbasid Revolution, also called the Movement of the Men of the Black Raiment, was the overthrow of the Umayyad Caliphate (661–750 CE), the second of the four major Caliphates in early Islamic history, by the third, the Abbasid Caliphate (750–1517 CE). Coming to power three decades after the death of the Islamic prophet Muhammad and immediately after the Rashidun Caliphate, the Umayyads were an Arab empire ruling over a population which was overwhelmingly non-Arab. Non-Arabs were treated as second-class citizens regardless of whether or not they converted to Islam, and this discontent cutting across faiths and ethnicities ultimately led to the Umayyads' overthrow. The Abbasid family claimed to have descended from al-Abbas, an uncle of Muhammad.
The revolution essentially marked the end of the Arab empire and the beginning of a more inclusive, multiethnic state in the Middle East. Remembered as one of the most well-organized revolutions during its period in history, it reoriented the focus of the Muslim world to the east.