The Umayyad Caliphate (661–750 CE) was the second caliphate established after the death of the Islamic prophet Muhammad. The caliphate was ruled by the Umayyad dynasty, also known as the Umayyads (Arabic: ٱلْأُمَوِيُّون, al-ʾUmawīyūn, or بَنُو أُمَيَّة, Banū ʾUmayya, "Sons of Umayya"). Uthman ibn Affan (r. 644–656), the third of the Rashidun caliphs, was also a member of the clan. The family established dynastic, hereditary rule with Muawiya ibn Abi Sufyan, long-time governor of Greater Syria, who became caliph after the end of the First Fitna in 661. After Mu'awiya's death in 680, conflicts over the succession resulted in the Second Fitna, and power eventually fell to Marwan I, from another branch of the clan. Syria remained the Umayyads' main power base thereafter, with Damascus as their capital.

The Umayyads continued the Muslim conquests, conquering Ifriqiya, Transoxiana, Sind, the Maghreb and Hispania (al-Andalus). At its greatest extent, the Umayyad Caliphate covered 11,100,000 km² (4,300,000 sq mi), making it one of the largest empires in history in terms of area. The dynasty was toppled by the Abbasids in 750. Survivors of the dynasty established themselves in Cordoba which, in the form of an emirate and then a caliphate, became a world centre of science, medicine, philosophy and invention during the Islamic Golden Age.

The Umayyad Caliphate ruled over a vast multiethnic and multicultural population. Christians, who still constituted a majority of the caliphate's population, and Jews were allowed to practice their own religion but had to pay the jizya (poll tax) from which Muslims were exempt. Muslims were required to pay the zakat tax, which was earmarked explicitly for various welfare programmes for the benefit of Muslims or Muslim converts. Under the early Umayyad caliphs, prominent positions were held by Christians, some of whom belonged to families that had served the Byzantines. The employment of Christians was part of a broader policy of religious accommodation that was necessitated by the presence of large Christian populations in the conquered provinces, as in Syria. This policy also boosted Mu'awiya's popularity and solidified Syria as his power base. The Umayyad era is often considered the formative period in Islamic art.