Black standard

The Black Banner or Black Standard (Arabic: راية السوداء‎‎ rāyat as-sawdāʾ, also known as راية العقاب rāyat al-ʿuqāb " of the " or simply as ‎ ar-rāya "the banner") is one of the flags flown by Muhammad in Islamic tradition. It was historically used by Abu Muslim in his uprising leading to the pro-Shia Abbasid Revolution in 747 and is therefore associated with the Abbasid Caliphate in particular. It is also a symbol in Islamic eschatology (heralding the advent of the Mahdi).

The Black Banner has been used in contemporary Islamism and jihadism since the late 1990s.

Before Islam, visible standards were used at least in the Roman army to identify the core of the legion, the Eagles. By the mid-600s, the Arabs were using standards for the same purpose. Among the Arabs the rāya was a square banner; not to be confused with the liwāʾ or ʿalam, an identifying mark like a red turban.

Islamic tradition states that the Quraysh had a black liwāʾ and a white-and-black rāya. It further states that Muhammad had an ʿalam in white nicknamed "the Young Eagle" (العقاب al-ʿuqāb); and a rāya in black, said to be made from his wife Aisha's head-cloth. This larger flag was known as the Eagle.

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Wikipedia