Umayyad Caliphate

The Umayyad Caliphate was the second of the caliphates established after the death of Muhammad, founded in 661 by Mu'awiya ibn Abi Sufyan following the First Fitna and the assassination of Ali. Ruled by the Umayyad dynasty from a power base in Syria, the caliphate governed first from Damascus and, in its final years, from Harran. Continuing the early Muslim conquests, it expanded to control the Maghreb, Transoxiana, Sindh and Hispania, and at its greatest extent under Caliph Umar II around 720 it covered between roughly 13 and 15 million square kilometers, making it one of the largest empires in history by geographical size. The caliphate governed a multiethnic, multicultural population in which Christians and Jews paid a poll tax while Muslims paid a religious charitable tax, and its era is considered the formative period of Islamic art. The Umayyad dynasty was overthrown by the Abbasids in 750; surviving members of the family fled west and established first an emirate and later a caliphate of their own at Cordoba in al-Andalus.