The Umayyads, or Banu Umayya, were a clan of the larger Quraysh tribe, which dominated Mecca in the pre-Islamic era. The Quraysh derived prestige among the Arab tribes through their protection and maintenance of the Ka'aba, which at the time was regarded by the largely polytheistic Arabs across the Arabian Peninsula as their most sacred sanctuary. A certain Qurashi tribesman, Abd Manaf ibn Qusayy, who based on his place in the genealogical tradition would have lived in the latter half of the 5th century, was apparently charged with the maintenance and protection of the Ka'aba and its pilgrims. These roles passed to his sons Abd Shams, Hashim and others. Abd Shams was the father of Umayya, the eponymous progenitor of the Umayyads.
Umayya succeeded Abd Shams as the qāʾid (wartime commander) of the Meccans. This position was apparently an occasional political post whose holder oversaw the direction of Mecca's military affairs in times of war instead of an actual field command. This proved instructive as later Umayyads were known for possessing considerable political and military organizational skills. Historian Giorgio Levi Della Vida suggests that information in Muslim traditional sources about Umayya, as with all the ancient progenitors of the tribes of Arabia, "be accepted with caution", but "that too great skepticism with regard to tradition would be as ill-advised as absolute faith in its statements". Della Vida further asserts that since the Umayyads who appear at the beginning of Muslim history in the early 7th century were no later than third-generation descendants of Umayya, the latter's existence is quite plausible.
By circa 600, the Quraysh had developed trans-Arabian trade networks, organizing caravans to Syria in the north and Yemen in the south. The Banu Umayya and the Banu Makhzum dominated these trade networks and developed economic and military alliances with the nomadic Arab tribes that controlled the northern and central Arabian desert expanses, gaining them a degree of political power in Arabia.
Opposition and embrace of Islam
When the Islamic prophet Muhammad, a member from the Banu Hashim, a politically weaker and less wealthy clan of the Quraysh related to the Banu Umayya through their shared ancestor, Abd Manaf, began his religious teachings in Mecca, he was opposed by most of the Quraysh. He ultimately found support from the inhabitants of Medina and relocated there with his followers in 622. The descendants of Abd Shams, including the Umayyads, were among the principal leaders of Qurashi opposition to the Islamic prophet Muhammad, a member of the Banu Hashim. They superseded the Banu Makhzum led by Abu Jahl as a result of the heavy losses that its leadership incurred fighting the Muslims at the Battle of Badr in 624. An Umayyad chieftain, Abu Sufyan, thereafter became the leader of the Meccan army that fought the Muslims under Muhammad at the battles of Uhud and the Trench.
Abu Sufyan and his sons, along with most of the Umayyads, ultimately embraced Islam toward the end of Muhammad's life, following the Muslim victory over the Meccans at the Battle of Hunayn in 629. To secure the loyalty of certain prominent Umayyad leaders, including Abu Sufyan, Muhammad offered them gifts and positions of importance in the nascent Muslim state. He installed another member of the clan, Attab ibn Asid ibn Abi'l-'Is, as the first governor of Mecca. Though Mecca retained its paramountcy as a religious center, Medina continued to serve as the political center of the Muslims. Abu Sufyan and the Banu Umayya relocated to the city to maintain their growing political influence.
Following Muhammad's death in 632, a succession crisis ensued and nomadic tribes throughout Arabia that had embraced Islam defected from the nascent, Medina-based Muslim state. Abu Bakr, trusted by the Ansar and the Muhajirun (Muhammad's initial supporters from Medina and Mecca, respectively) as one of Muhammad's oldest friends and earliest converts to Islam and accepted by the late converts from the Quraysh as a native Meccan who assured their influential role in state matters, was elected caliph (paramount political and religious leader of the Muslim community). Abu Bakr showed favor to the Umayyads by awarding them a prominent role in the Muslim conquest of Syria. He first assigned the Umayyad Khalid ibn Sa'id ibn al-As as commander of the expedition, then replaced him with four commanders, among whom was Yazid, the son of Abu Sufyan, who owned property and maintained trade networks in Syria.
Abu Bakr's successor, Caliph Umar (r. 634–644), though he actively curtailed the influence of the Qurayshi elite in favor of Muhammad's earlier supporters in the administration and military, did not disturb the growing foothold of Abu Sufyan's sons in Syria, which was all but conquered by 638. When his overall commander over the province, Abu Ubayda ibn al-Jarrah, died in 639, he appointed Yazid governor of its Damascus, Palestine and Jordan districts. Yazid died shortly after and Umar installed his brother Mu'awiya in his place. Umar's exceptional treatment of Abu Sufyan's sons may have stemmed from his respect for the family, their burgeoning alliance with the powerful Banu Kalb tribe as a counterbalance to the influence of the Himyarite tribes who entered the Homs district during the conquest or the lack of a suitable candidate at the time, particularly amid the plague of Amwas which had already killed Abu Ubayda and Yazid.
Empowerment by Caliph Uthman
Uthman ibn Affan, a wealthy Umayyad merchant, early convert to Islam and son-in-law and close companion of Muhammad succeeded Caliph Umar upon the latter's death in 644. Uthman initially kept his predecessors' appointees in their provincial posts, but gradually replaced many with Umayyads or his maternal kinsmen from the Banu Umayya's parent clan, the Banu Abd Shams: Mu'awiya, who had been appointed governor of Syria by Umar, retained his post; al-Walid ibn Uqba and Sa'id ibn al-'As were successively appointed to Kufa, one of the two main garrisons and administrative centers of Iraq; and Marwan ibn al-Hakam became his chief adviser. Though a prominent member of the clan, Uthman is not considered part of the Umayyad dynasty because he was chosen by consensus (shura) among the inner circle of Muslim leadership and never attempted to nominate an Umayyad as his successor. Nonetheless, as a result of Uthman's policies, the Umayyads regained a measure of the power they had lost after the Muslim conquest of Mecca.
The assassination of Uthman in 656 became a rallying cry for the Qurashi opposition to his successor and cousin of Muhammad, Caliph Ali ibn Abi Talib of the Banu Hashim. The Qurashi elite did not hold Ali responsible, but opposed his accession under the circumstances of Uthman's demise. Following their defeat at the Battle of the Camel near Basra, which saw the deaths of their leaders Talha ibn Ubayd Allah and al-Zubayr ibn Awwam, both potential contenders of the caliphate, the mantle of opposition to Ali was taken up chiefly by Mu'awiya. Initially, he refrained from openly claiming the caliphate, focusing instead on undermining Ali's authority and consolidating his position in Syria, all in the name of avenging Uthman's death. Mu'awiya and Ali with their respective Syrian and Iraqi supporters fought a stalemate at the Battle of Siffin in 657. It ultimately led to an indecisive arbitration, which ultimately weakened Ali's command over his partisans, while raising the stature of Mu'awiya as Ali's equal. As Ali was bogged down combating his former partisans, who became known as the Kharijites, Mu'awiya was recognized as caliph by his core supporters, the Syrian Arab tribes, in 659 or 660. When Ali was assassinated by a Kharijite in 661, Mu'awiya took the opportunity to march on Kufa where he ultimately compelled Ali's son Hasan to cede caliphal authority and gain recognition from the region's Arab tribal nobility. As a result, Mu'awiya became widely accepted as caliph, though opposition by the Kharijites and some of Ali's loyalists persisted, albeit at a less consistent level.
Establishment of caliphate in Damascus
The reunification of the Muslim community under Mu'awiya's leadership marked the establishment of the Umayyad dynasty. Based on the accounts of the traditional Muslim sources, Hawting writes that
... the Umayyads, leading representatives of those who had opposed the Prophet [Muhammad] until the latest possible moment, had within thirty years of his death reestablished their position to the extent that they were now at the head of the community which he had founded.