Ali in the context of "Umayyad dynasty"

Sunni Islam is the largest branch of Islam and the largest religious denomination in the world. It holds that Muhammad did not appoint any successor and that his closest companion Abu Bakr (r. 632–634) rightfully succeeded him as the caliph of the Muslim community, being appointed at the meeting of Saqifa. This contrasts with the Shia view, which holds that Muhammad appointed Ali ibn Abi Talib (r. 656–661) as his successor. Nevertheless, Sunnis revere Ali, along with Abu Bakr, Umar (r. 634–644) and Uthman (r. 644–656) as 'rightly-guided caliphs'.

The term Sunni means those who observe the sunna, the practices of Muhammad. The Quran, together with hadith (especially the Six Books) and ijma (scholarly consensus), form the basis of all traditional jurisprudence within Sunni Islam. Sharia legal rulings are derived from these basic sources, in conjunction with consideration of public welfare and juristic discretion, using the principles of jurisprudence developed by the four legal schools: Hanafi, Hanbali, Maliki and Shafi'i.

The Rashidun Caliphate (Arabic: ٱلْخِلَافَةُ ٱلرَّاشِدَةُ, romanized: al-Khilāfah ar-Rāšidah) is the early Islamic polity led by the first four successive caliphs (lit. "successors") Abu Bakr, Umar, Uthman and Ali, collectively the Rashidun, or "Rightly Guided" caliphs. These early caliphs led the Muslim community from the death of the Islamic prophet Muhammad in 632 CE to the foundation of the Umayyad Caliphate in 661 CE.

The title Rashidun stems from the Sunni Islamic belief that the caliphs were "rightly guided". Endowed with superior piety and wisdom, their era is regarded in Sunni Islam as a "golden age", second only to the lifetime of the Prophet Muhammad in sanctity and in providing moral and religious guidance. Sunni Muslims consider the "rightly guided" reign of the first four caliphs as a model to be followed and emulated from a religious point of view. The term Rashidun is not used by Shia Muslims, who make up 10–15% of the global Muslim population, as they reject the rule of the first three caliphs as illegitimate.

The Fatimid Caliphate (/ˈfætɪmɪd/; Arabic: الخلافة الفاطمیّة, romanized: al-Khilāfa al-Fāṭimiyya), also known as the Fatimid Empire, was a caliphate extant from the tenth to the twelfth centuries CE under the rule of the Fatimids, an Isma'ili Shi'a dynasty. Spanning a large area of North Africa and West Asia, it ranged from the western Mediterranean in the west to the Red Sea in the east. The Fatimids traced their ancestry to the Islamic prophet Muhammad's daughter Fatima and her husband Ali, the first Shi'a imam. The Fatimids were acknowledged as the rightful imams by different Isma'ili communities as well as by denominations in many other Muslim lands and adjacent regions. Originating during the Abbasid Caliphate, the Fatimids initially conquered Ifriqiya (roughly present-day Tunisia and north-eastern Algeria). They extended their rule across the Mediterranean coast and ultimately made Egypt the center of the caliphate. At its height, the caliphate included—in addition to Egypt—varying areas of the Maghreb, Sicily, the Levant, and the Hejaz.

Between 902 and 909, the foundation of the Fatimid state was realized under the leadership of da'i (missionary) Abu Abdallah, whose conquest of Aghlabid Ifriqiya with the help of Kutama forces paved the way for the establishment of the Caliphate. After the conquest, Abdallah al-Mahdi Billah was retrieved from Sijilmasa and then accepted as the Imam of the movement, becoming the first Caliph and founder of the dynasty in 909. In 921, the city of al-Mahdiyya was established as the capital. In 948, they shifted their capital to al-Mansuriyya, near Kairouan. In 969, during the reign of al-Mu'izz, they conquered Egypt, and in 973, the caliphate was moved to the newly founded Fatimid capital of Cairo. Egypt became the political, cultural, and religious centre of the empire and it developed a new and "indigenous Arabic culture". After its initial conquests, the caliphate often allowed a degree of religious tolerance towards non-Shi'a sects of Islam, as well as to Jews and Christians. However, its leaders made little headway in persuading the Egyptian population to adopt its religious beliefs.

Alawites (Arabic: العلويون, romanized: al-ʿAlawiyyūn) are an ethnoreligious group who live primarily in the Levant region in West Asia and follow Alawism, an offshoot of Shia Islam as a ghulat branch during the ninth century. Alawites venerate Ali ibn Abi Talib, the "first Imam" in the Twelver school, as a manifestation of the divine essence. It is the only ghulat sect still in existence today. The group was founded during the ninth century by Ibn Nusayr, who was a disciple of the tenth Twelver Imam, Ali al-Hadi, and of the eleventh Twelver Imam, Hasan al-Askari. For this reason, Alawites are also called Nusayris, although this term can be considered derogatory in the present day.

Surveys suggest Alawites represent an important portion of the Syrian population and are a significant minority in the Hatay Province of Turkey and northern Lebanon. There is also a population living in the village of Ghajar in the Golan Heights, where there had been two other Alawite villages (Ayn Fit and Za'ura) before the Six-Day War. The Alawites form the dominant religious group on the Syrian coast and towns near the coast, which are also inhabited by Sunnis, Christians, and Ismailis. They are often confused with the Alevis, a religious group in Turkey that shares certain similarities with the Alawites but has key differences.

The Saqifa (Arabic: سَقِيفَة, romanized: Saqīfah) of the Banu Sa'ida clan refers to the location of an event in early Islam where some of the companions of the Islamic prophet Muhammad pledged their allegiance to Abu Bakr as the first caliph and successor to Muhammad shortly after his death in 11 AH (632 CE). The Saqifa meeting is among the most controversial events in early Islam, due to the exclusion of a large number of Muhammad's companions, including his immediate family and notably Ali, his cousin and son-in-law. The conflicts that arose soon after Muhammad's death are considered to be the main cause of the current division among Muslims. Those who accepted Abu Bakr's caliphate were later labeled Sunnis, while the supporters of Ali's right to caliphate were later labeled Shia.

Shia Islam is the second-largest branch of Islam. It holds that Muhammad designated Ali ibn Abi Talib (r. 656–661) as both his political successor (caliph) and as the spiritual leader of the Muslim community (imam). However, his right is understood to have been usurped by a number of Muhammad's companions at the meeting of Saqifa, during which they appointed Abu Bakr (r. 632–634) as caliph instead. As such, Sunni Muslims believe Abu Bakr, Umar (r. 634–644), Uthman (r. 644–656) and Ali to be 'rightly-guided caliphs', whereas Shia Muslims regard only Ali as the legitimate successor.

Shia Muslims believe that the imamate continued through Ali's sons, Hasan and Husayn, after which various Shia branches developed and recognized different imams. They revere the ahl al-bayt, the family of Muhammad, maintaining that they possess divine knowledge. Shia holy sites include the shrine of Ali in Najaf, the shrine of Husayn in Karbala, and other mausoleums of the ahl al-bayt. Later events, such as Husayn's martyrdom in the Battle of Karbala (680 CE), further influenced the development of Shia Islam, contributing to the formation of a distinct religious sect with its own rituals and shared collective memory.