The term Shiʿa literally means followers, party, group, associate, partisan, or supporters. Expressing these meanings, Shiʿa occurs a number of times in the Quran (e.g., surahs 19:69, 28:15, and 37:83). Technically the term refers to those Muslims who derive their religious code and spiritual inspiration, after the Prophet, from Muhammad’s descendants, the Ahl al-Bayt (literally, people of the house). The focal point of Shi’ism is the source of religious guidance after the Prophet; although the Sunnis accept it from the sahaba (companions) of the Prophet, the Shiʿa restrict it to the members of the ahl al-bayt.

Rashidun PeriodEdit

The origin of the Shiʿa movement can be traced to the Medinan period of the Prophet's life. Some prominent Companions saw the Prophet's cousin ʿAli ibn Abi Talib as his wasi (legatee) and the imam to lead the community after him. Soon after the death of the prophet, at the beginning of the Rashidun period (632–661), this special regard for ʿAli found expression when he was denied the leadership of the community. The early supporters of ʿAli constituted the first nucleus of the Shiʿa.

However, after the initial defeat of ʿAli's supporters and his own recognition of Abu Bakr's administration six months later, Shiʿa tendencies lost most of their open and active manifestations. This lasted through the caliphates of Abu Bakr and his successor, ʿUmar (r. 632–644). After the death of ʿUmar, Shiʿa feelings once again found expression in the protest made by ʿAli's supporters when ʿUthman was declared the third caliph. The office was first offered to ʿAli on the condition that he follow the precedents established by the first two caliphs; ʿAli refused this condition, and ʿUthman accepted it. If ideological differences between the Shiʿa and Sunnis date back to the election of Abu Bakr, the differences in legal matters, at least theoretically, must be dated from ʿAli's refusal to follow the precedents of the first two caliphs. This refusal was thus a cornerstone in the development of Shiʿi legal thought, which would come to include a variety of forms (including Ithna ʿAshari [or Twelver], Ismaʿili, and Zaydi), although it took some time for the Sunni and Shiʿi legal systems to become clearly distinguishable.

Socioeconomic issues also played a part in the development of Shiʿi Islam. Unlike the first two caliphs, ʿUthman belonged to the powerful clan of the Umayyads which, in his accession, found an opportunity to regain its former political importance. Within a few years of ʿUthman's accession, the Umayyads claimed all the positions of power and advantage and appropriated to themselves the immense wealth of the empire at the expense of the masses. The resulting social and economic disequilibrium aroused the resentment of various sectors of the population. The discontent exploded into revolt, and the caliph was killed in 656. Populist opposition to the Umayyad aristocracy thus became involved with support for ʿAli, who accepted the caliphate, reportedly with great reluctance. ʿAli's accession was, however, strongly resisted by the Umayyads, represented by Muʿawiya and some of the Companions who sought the position for themselves. This resulted in the first civil wars in Islam and ultimately led to ʿAli's assassination in 661.

The sixteen-year period beginning with the caliphate of ʿUthman and ending with the assassination of ʿAli differed markedly from the preceding period in the development of Shi’ism in a number of ways: it encouraged the Shiʿi tendencies to become more conspicuous, active, and sometimes violent, and a number of political, geographical, and economic considerations coalesced around the Shiʿi identity, broadening its sphere of activity. The emergence of political Shiism at this stage is thus characterized both by the increase in its influence and numbers and by its sudden and rapid growth thereafter.

Umayyad and Abbasid PeriodsEdit

The Abbasid era (750–945) witnessed consolidation of the Shiʿi identity. During the first twenty years of Umayyad rule under Muʿawiya, Hasan, the elder son of ʿAli who was acclaimed caliph by the majority of the Muslims, was forced to abdicate. Some of the ardent supporters of the Shiʿi cause were executed, cursing ʿAli from pulpits all over the empire was proclaimed by the governors to be an official duty, and the Shiʿa were oppressed and terrorized. But the single event that crystallized the nature of official Shi’ism was the martyrdom of Hussain in 681 at Karbala. Hussain, the only surviving grandson of the Prophet and the focus of Shiʿi aspirations, along with eighteen male members of his family and many companions, was brutally killed, and the women and children of his caravan were made captives to be humiliated in the markets and courts of Kufa and Damascus.

The tragedy of Karbala became the most effective agent in the propagation of Shi’ism. It gave to Shiʿi Islam its ethos of passion, in expressing the love (walayah) for Ahl al-Bayt and a willingness to suffer persecution for the sake of justice and piety. Within a year, the tragedy gave rise to a movement known as Tawwabun (Penitents), three thousand of whom sacrificed their lives fighting the overwhelming force of the Umayyads in repentance for their inability to help Hussain in his hour of trial. This passionate act of self-sacrifice took place without a leader from among the ahl al-bayt and thus marks the emergence of Shi’ism as an independent and self-sustaining movement.

The death of Hussain and the quiescent attitude of his only surviving son, ʿAli Zayn al-ʿAbidin, however, marked the first conflict over the leadership of the followers of the ahl al-bayt and their division into various groups. The Shiʿa in Kufa, especially the mawali (the non-Arabs and the downtrodden masses) wanted an active movement which could relieve them from the oppressive rule of the Umayyads. Mukhtar ibn Abi ʿUbaydah al-Thaqafi, a Shiʿa activist, began to promote ʿAli's third son, Muhammad ibn al-Hanafiyah, born of a Hanafi woman, as the Mahdi, who would save the people from oppression. This is the first recorded reference to the Mahdi. The Shiʿa saw a ray of hope in the messianic role advocated by Mukhtar for Ibn al-Hanafiyah, and they followed him as their Imam-Mahdi, abandoning Zayn al-ʿAbidin. Mukhtar’s uprising was put down in 686, and Mukhtar himself was killed, but the propaganda on behalf of Ibn al-Hanafiyah continued, and when he died in 700 a group of his followers, known as Kaysaniyah, believed that he had not died but had gone into “occultation” or been “hidden” and would return. The idea of the Mahdi, often equated with the Imam, and the concepts of ghaybah (occultation) and rajʿah (return) thus became integral to Shiʿi thought.

After Mukhtar’s uprising, the first ʿAlid of the Hussainid line who rose against the Umayyads was Zayd, the second son of Zayn al-ʿAbidin. Zayd and his followers wanted no quiescent or Hidden Imam, like al-Baqir and Ibn al-Hanafiyah. In their eyes, the imam, although he had to be a descendant of ʿAli and Fatima, could not claim allegiance unless he asserted his imamate publicly and, if necessary, fought for it. Zayd's activist policy toward the imamate and his adoption of the rationalist Muʿtazilah theological doctrines secured him Shiʿi support, and his acceptance of the legitimacy of the first two caliphs gained him the full sympathy of traditionalist circles. Zayd's revolt, however, was unsuccessful. He and many of his followers were killed in 740, and his son Yahya, who continued his father's activities for three years, met the same fate in 743.

After the collapse of Zayd's revolt, the only serious Shiʿi uprising to take place during the Umayyad period was that of the Abbasids, which began as a manifestation of the Shiʿi cause. The agents of the Abbasids called the people to rise in the name of an imam to be chosen from among the ahl al-bayt. To the extremists of the Kaysaniyah—the followers of Ibn al-Hanafiyah and his son Abu Hashim—the activists of the Zaydiyah, and the other groups of the Shiʿa, this implied an ʿAlid, so they supported the Abbasids wholeheartedly. The Abbasids thus succeeded in overthrowing the Umayyad regime. Once in power, they realized that the Shiʿa would not accept them as legitimate rulers, so they turned to the ahl al-hadith (people of the hadith, i.e., Sunnis) for their religious support and began to persecute the Shiʿa. The series of Zaydi revolts, particularly among ʿAlids of the Hasanid line, which had begun toward the end of the Umayyad era, continued into the Abbasid period. Muhammad al-Nafs al-Zakiyah, a great-grandson of Hasan who had long coveted the role of Mahdi for himself, rose against the Abbasids, but he and his brother Ibrahim were defeated and killed in 762. Some of al-Nafs al-Zakiyah's followers believed that he was not dead but had gone into occultation and would return.

During the formative phase of Shi’ism, three major trends of thought—activism, extremism, and legitimism—dominated the Shiʿi perception of the imamate. For the early period, however, it is difficult to identify well-organized groups representing each of these trends, as there was considerable overlap among their beliefs. Activists like the Kaysaniyah, for example, sometimes adopted extremist ideas. The extremists, known as ghulat (exaggerators) because of their ascription of divinity to the Imams, often resorted to activist methods. But the ghulat, who were identified as Shiʿa by Sunni scholars of heresy, remained a minority that was rejected by the main body of the Shiʿa condemned by their Imams. In the course of history, however, extremists and other small branches died out or were merged into the three main branches which have survived into the twenty-first century.

The Zaydiyah, followers of Zayd ibn ʿAli ibn al-Hussain, are mainly in Yemen with smaller numbers in Iraq and parts of Africa. They represent the activist groups of the early Shiʿa, as Zayd believed that the Imam ought to be a ruler of the state and therefore must fight for his rights.

The Ismaʿiliyah, named after Ismaʿil, the eldest son of Imam Jaʿfar al-Sadiq, who predeceased his father, declared Ismaʿil's son Muhammad to be their seventh Imam, instead of following Jaʿfar's second son, Musa al-Kazim. The Ismaʿiliyah are also known as the Batiniyah (the internal), that is, those who maintained the central role of the esoteric aspects of Islamic revelation in their religious system. Ismaʿilis occasionally rose to great political and religious prominence, and they founded the Fatimid Empire (909–1171).

The majority of the Shiʿa belong to the Twelvers, the Ithna ʿAshariyah, whose theological position is regarded as moderate. They represent the legitimist or central body of the Shiʿa who believe in twelve Imams beginning with ʿAli, followed by his two sons, Hasan and Hussain, as the second and the third Imams, respectively. After Hussain, according to Twelver Shiʿa, the imamate remained with his descendants until it reached the twelfth Imam, Muhammad al-Mahdi, who went into occultation to return at the end of time as the messianic Imam to restore justice and equity on earth.

The consolidation of the Ithna ʿAshari position was accomplished by Imam Jaʿfar al-Sadiq, the sixth Imam of the quiescent Hussainid branch, who expounded his theory of the imamate based on naṣ, the explicit designation of his successor by the previous Imam, and the special knowledge of religion passed down in the family from generation to generation. With the efforts of Jaʿfar, the quiescent line of the Hussainid Imams regained the prominence it had lost after the death of Hussain. Jaʿfar was surrounded by traditionalists who played an important role in establishing the Shiʿi legal and theological system. By the time of Jaʿfar's death in 765, the Shiʿa (later to become the Twelvers) were fully equipped in all branches of religion and had acquired a distinctive character. The remaining six Imams of the Twelvers’ line living under the Abbasids in varying circumstances further strengthened Imami Shi’ism until the twelfth Imam, Muhammad al-Mahdi, went into occultation.

Buyid PeriodEdit

The Buyids (945–1055) accorded the Shiʿa the most favorable conditions for elaboration and standardization of their tenets. In this period compilation of the major collections of Shiʿa hadith and formulation of Shiʿa law took place. This elaboration began with Muhammad ibn Yaʿqub al-Kulayni (d. 490), author of the monumental Usul al-kafī (the sufficient fundamentals), who was followed by such figures as Ibn Babuyah, also called Shaykh al-Saduq (d. 991), Shaykh al-Mufid (d. 1022), and Shaykh al-Taʿifah, or Muhammad ibn al-Hasan al-Ṭusi (d. 1067), by whom the principal doctrinal works of Shiʿi theology and religious sciences were finally established. This was also the period of other renowned Shiʿi scholars, such as al-Sharif al-Razi (d. 1015)—who compiled the sermons and sayings of ʿAli—and his brother, Murtaza ʿAlam al-Huda (d. 1044).

These intellectual activities continued after the fall of the Buyids through such Shiʿi scholars as Fazl al-Tabarsi (d. 1153), known for his monumental Quranic commentary; Razi al-Din ʿAli ibn al-Ta’us (d. 1266), theologian and gnostic; Nasir al-Din al-Ṭusi (d. 1273); ʿAllamah Ḥilli (d. 1326); and Haydar al-Amuli (d. after 1385), who established a new system of rational theology.

It was also in the Buyid period that two popular Shiʿi commemorations were instituted in Baghdad: Ashura, marking the martyrdom of Imam Hussain on the tenth of the month Muharram, which was observed with great religious fervor and zeal; and the Festival of Ghadir, commemorating the Prophet's nomination of ʿAli as his successor at Ghadir al-Khumm. It was also during this period that public mourning ceremonies for Hussain were initiated, shrines were built for the Imams, and the custom of pilgrimage to these shrines was more popularly established.

By the end of the Buyid era Shiism's basic beliefs had been completely formulated, leaving to the future only elaborations, interpretations, rationalizations, and certain adaptations and additions. Among the scholars who have enriched Shiʿi literature over the past eight hundred years—especially in philosophy, theology, and law during the Mongol, Ṣafavid, and Qajar periods—were such great figures of the Ṣafavid period as Mir Damad (d. 1631) and Mulla Sadra (d. 1640), masters of metaphysics with whom Islamic philosophy reached a new peak; Baha’ al-Din al-ʿAmili, theologian and mathematician; and the two Majlisis, the second, Muhammad Baqir, being the author of the largest compendium of the Shiʿi sciences, the Bihar al-anwar (Oceans of Light).

Although Ithna ʿAshari Shiism attained its final position under the Buyids who ruled over Baghdad and Iran, the Ismaʿiliyah and the Zaydiyah also consolidated their doctrinal positions at roughly the same time. The Ismaʿilis controlled Egypt, southern Syria, much of North Africa, and the Hejaz, and the Zaydis established their rule in northern Iran and Yemen. This political supremacy provided the Ismaʿiliyah and the Zaydiyah with opportunities to elaborate and standardize their doctrinal positions. By the end of the tenth century, all three branches of Shiism were thus firmly enough established to withstand the vicissitudes of history and the stresses of the sectarian role into which they were pushed by the Sunni majority.


  • Classic histories such as Muhammad ibn Jarīr al-Ṭabarī's Tārīkh al-rusul wa-al-mulūk (History of the Prophets and the Kings) (2d ed., 10 vols., Cairo, 1979; translated into English as The History of al-Ṭabarī, Albany: State University of New York, 1985–), Aḥmad ibn Abī Yaʿqūb Yaʿqūbī's Tārīkh al-Yaʿqūbī (Yaʿqūbī's History) (2 vols., Beirut, 1980), and Abū Ḥanīfah Aḥmad ibn Dawūd Dīnawārī's Al-akhbār al-tiwāl (The General History), edited by ʿAbd al-Munʿim Amir (Cairo, 1960) give historical accounts of the political events and religious thought of the first three centuries of Islam.
  • Some Shīʿī and Sunni works on heresies are Abū al-Ḥasan ʿAlī ibn Ismāʿīl al-Ashʿarī's Maqālāt al-Islāmīyin wa-ikhtilāf al-musallin (Islamic Treatises and Controversies of the Worshippers), edited by Muhammad Muḥyīʿ al-Dīn ʿAbd al-Ḥamīd (2d rev. ed., Cairo, 1969), Abū Fatḥ al-Shahrastānī's Al-milal wa-al-nihal (Sects and Creeds), edited by Muhammad Sayyid Kīlānī (2 vols., Beirut, 1982), and al-Ḥasan ibn Mūsā Nawbakhti's Firaq al-Shiʿa (Shīʿī Sects; 2d ed., Beirut, 1984); the first two give the Sunni account and the third the Shiʿa view of various Shīʿī sects which emerged in the first two centuries of Islam.
  • Theological and creedal works of the Shiʿa include Shaykh Ṣadūq ibn Bābūyah al-Qummī's Risālāt al-iʿtiqād (Treatises on the Creed, translated by A. A. A. Fyzee as A Shiʿite Creed, London, 1942), Ḥasan ibn Yūsuf al-Ḥillī's Al-Bāb al-Ḥādī ʿAshar (The Eleventh Chapter, translated by W. M. Miller as A Treatise on the Principles of Shīʿ Theology, London, 1928), and Muhammad Ḥusayn Ṭabāṭabāʿī's Shiʿa dār Islām (edited and translated by Seyyed Hossein Nasr as Shiʿite Islam, Albany, N.Y.: State University of New York Press, 1975); the first two provide the most authentic Shīʿī creed by scholars of the tenth century and the last a philosophical exposition by a modern scholar.
  • Several modern studies include Syed Husain M. Jafri'sOrigins and Early Development of Shiʿah Islam (London: Longman, 1979), which examines the development of Shīʿī thought in historical perspective until the time of Imam Jaʿfar; and Moojan Momen's An Introduction to Shiʿi Islam: The History and Doctrines of Twelver Shiʿism (New Haven, Conn. Yale University Press, 1987), which mainly gives political and dynastic history up to modern times.
  • After the 1979 Islamic Revolution in Iran and the 2003 Iraq War that freed that country's Shīʿī clergy from Baʿth regime constraints, several useful books were published on the mobilization of Persian and Arab Shiʿa, among them Robert Gleave, Inevitable Doubt: Two Theories of Shīʿī Jurisprudence (Leiden: E. J. Brill, 2000); Kafkzli Seyyed Javad Miri Meynagh, Unknown: An Imami Shia's Quest for Enlightening Salvation in the Age of Major Occultation (New York: Xlibris, 2003); Raza Ali Hasan, Grieving Shias (Riverdale-on-Hudson, N.Y.: Sheep Meadow Press, 2006); Yitzhak Nakash, Reaching for Power: The Shiʿa in the Modern Arab World (Princeton: Princeton University Press, 2006); Vali Nasr, The Shia Revival: How Conflicts within Islam Will Shape the Future (New York: Norton, 2007); and Jaʿfar Sobhani and Reza Shah-Kazemi, Doctrines of Shiʿi Islam (Qom, Iran: Imam Sadeq Institute, 2003).