The Umayyad Caliphate is the second of the four major Islamic caliphates established after the death of Muhammad.

The caliphate is centered on the Umayyad dynasty (Arabic: Banū ʾUmayya, "Sons of Umayya"), hailing from Mecca.

The Umayyad family had first come to power under the third Caliph, Uthman ibn Affan (r. 644–656), but the Umayyad regime is founded by Muawiya ibn Abi Sufyan, longtime governor of Syria, after the end of the First Muslim Civil War in 661 CE/41 AH.

Syria remains the Umayyads' main power base hereafter, and Damascus is their capital.

The Umayyads continue the Muslim conquests, incorporating the Caucasus, Transoxiana, Sindh, the Maghreb and the Iberian Peninsula (Al-Andalus) into the Muslim world.

At its greatest extent, the Umayyad Caliphate covers 5.79 million square miles (15,000,000 km2), making it the largest empire the world had yet seen, and the fifth largest ever to exist.

At the time, the Umayyad taxation and administrative practice are perceived as unjust by some Muslims.

While the non-Muslim population has autonomy, their judicial matters are dealt with in accordance with their own laws and by their own religious heads or their appointees.

They pay a poll tax for policing to the central state.

Muhammad was said to have stated explicitly during his lifetime that each religious minority should be allowed to practice its own religion and govern itself and the policy had on the whole continued.

The welfare state for both the Muslim and the non-Muslim poor started by Omar had also continued.

Muawiya's wife Maysum (Yazid's mother) is a Christian.

The relations between the Muslims and the Christians in the state are good.

The Umayyads are involved in frequent battles with the Christian Byzantines without being concerned with protecting their rear in Syria, which has remained largely Christian like many other parts of the empire.

Prominent positions are held by Christians, some of whom belong to families that had served in Byzantine governments.

The employment of Christians is part of a broader policy of religious tolerance that is necessitated by the presence of large Christian populations in the conquered provinces, especially in Syria.

This policy also boosts Muawiya's popularity and solidifies Syria as his power base.

The rivalries between the Arab tribes cause unrest in the provinces outside Syria, most notably in the Second Muslim Civil War of 680–692 CE and the Berber Revolt of 740–743 CE.

During the Second Civil War, leadership of the Umayyad clan shifts from the Sufyanid branch of the family to the Marwanid branch.

As the constant campaigning exhausts the resources and manpower of the state, the Umayyads, weakened by the Third Muslim Civil War of 744–747 CE, are finally toppled by the Abbasid Revolution in 750 CE/132 AH.

A branch of the family flees across North Africa to Al-Andalus, where they established the Emirate, and later Caliphate, of Córdoba, which lasts until 1031 before falling due to the Fitna of al-Ándalus.