Before the advent of Islam, banners as tools for signaling had already been employed by the pre-Islamic Arab tribes and the Byzantines. Early Muslim army naturally deployed banners for the same purpose.[1] Early Islamic flag, however, greatly simplified its design by using plain color, due to the Islamic prescriptions on aniconism.[2] According to the Islamic traditions, the Quraysh had a black liwāʾ and a white-and-black rāya.[3] It further states that Muhammad had an ʿalam in white nicknamed "the Young Eagle" (Arabic: العقاب‎ al-ʿuqāb); and a rāya in black, said to be made from his wife Aisha's head-cloth.[4] This larger flag was known as " the Banner of the Eagle" (Arabic: الراية العقاب‎ al-rāyat al-ʻuqāb), as well as "the Black Banner" (Arabic: الراية السوداء‎ ar-rāyat as-sawdāʾ).[5] Other examples are the prominent Arab military commander 'Amr ibn al-'As using red banner,[6] and the Khawarij rebels using red banner as well.[7] Banners of the early Muslim army in general, however, employed a variety of colors, both singly and in combination.[8]