In Islamic eschatology, the Mahdi is a Messianic figure who, it is believed, will appear on Earth before the Day of Judgment, and will rid the world of wrongdoing, injustice and tyranny. People claiming to be the Mahdi have appeared across the Muslim world and throughout history since the birth of Islam.

A claimant Mahdi can wield great temporal, as well as spiritual, power: claimant Mahdis have founded states (e.g. the late 19th-century Mahdist State in Sudan), as well as religions and sects (e.g. Bábism, or the Ahmadiyya movement). The continued relevance of the Mahdi doctrine in the Muslim world was most recently emphasised during the 1979 seizing of the Grand Mosque in Mecca, Saudi Arabia, by up to 600 militants led by Juhayman al-Otaibi, who had declared his brother-in-law, Muhammad bin abd Allah al-Qahtani, the Mahdi.

Background Traditionally interest in "apocalyptic speculation", (with the appearance of the Mahdi being central), has been strongest among mainstream Twelver Shia, Isma'ili, and Sunni Muslims living on the "doctrinal and geographic margins"such as present day Morocco or Sudanbut was weaker in the heartland of Sunni Islam.Filiu, Apocalypse in Islam , 2011: p. 49

While at least in Shi'a Islam, waiting for the Mahdi "is hailed as a form of worship; joining him when he appears and fighting under his banner to fill the world with justice is an everyday aspiration of the faithful", so that more pious Muslims are naturally attracted to support for someone convincingly claiming to be a Mahdi, there is sometimes considerable clash between a claimant on the one hand, and orthodox believers and Islamic scholars on the other. In Iraq claimants have been condemned as "infidels, charlatans and liars", while in Iraq one self-proclaimed mahdi, Dia Abdul Zahra Kadim,Hardy, Roger (January 31, 2007). "Confusion surrounds Najaf battle". BBC.Roug, Louise; Fakhrildeen, Saad (January 30, 2007). "Religious cult targeted in fierce battle near Najaf". Los Angeles Times. and Ahmad al-Hassan, who claims the mahdi has appointed him his representative (wassi), both with militias, have both vigorously attacked Ayatollahs of Shi'i Islam.

Mahmoud Pargoo offers the explanation that according to Shīʿa hadiths, the mahdi "will bring a new religion, a new book and a new law"; making hard won Islamic learning and beloved, established religious rituals and institutions "redundant".

Eighth century

Abdallah ibn Mu'awiya Abdallah ibn Mu'awiya was a descendant of Ja'far ibn Abi Talib. At the end of 127 AH / AD 744 Shias of Kufa set up him as Imam. He revolted against Yazid III, the Umayyad Caliph, with the support of Shias of Kufa and Ctesiphon. He moved to west of Iran and Isfahan and Istakhr. He managed to control the west of Iran for two years. Finally, he was defeated by the caliph armies in AD 746–7 and fled to Harat in Khurasan. He allegedly died imprisoned by Abu Muslim, his rival. His followers did not believe his death and said that he went to occultation and he would return as Mahdi.

Muhammad ibn Isma'il Muhammad ibn Isma'il (740–813 CE), son of Isma'il ibn Ja'far (for whom Isma'ili sect of Islam was named),Filiu, Apocalypse in Islam , 2011: p. 50 did not claim to be a Mahdi, and most Isma'ili believe the line of Imams continued through his son Ahmad al-Wafi (Abadullah ibn Muhammad), but after his death was revered by his followers as "the seventh and last imam ... whose return was awaited under the signs and powers customarily ascribed to the Mahdi."

Tenth century In the tenth century the Isma'ili sect split into twothe Salamiyids, headquartered in Salamiyah and led by Abdullah al-Mahdi Billah; and the Qarmatians, centred in al-Hasa (Eastern Arabia)each proclaiming a Mahdi. The Qarmatians broke away from the Salamiyah after Abdullah al-Mahdi Billah (Salamiyid leader) proclaiming himself mahdi. About 30 years later, Qarmatian leader Abu Tahir al-Jannabi, proclaimed his own Mahdi, a "young prisoner", Abu'l-Fadl al-Isfahani.

Abdullah al-Mahdi Billah

In 899 CE, Abdullah al-Mahdi Billah (born Abdullah Sa'id) (r. 909–934), the head of the Isma'ili sect at the time, declared himself to be the Mahdi.The first caliph of the Fatimid state, established in 909, was one of few claimants who succeeded in establishing a state. (See Abū ʿAbd Allāh Muḥammad ibn Tūmart and Muhammad Ahmad bin Abdullah bin Fahal below). His authority as Mahdi was invoked to seize central Syria in 903, but his forces there were crushed by Iraqi troops.Filiu, Apocalypse in Islam , 2011: p. 51 His preacher, Abu 'Abdullah Al-Husayn Al-Shi'i, helped secure for him parts of north Africa using the support of the Berber locals some years later. The date of the apocalypse that was to follow the arrival of the Mahdi was "indefinitely postponed", and Abdullah was unable to deploy any of the supernatural powers he (in theory) possessed as Mahdithose who insisted he use them were dismissed, and sometimes put to death.

The Fatimids eventually "abandoned millenarian rhetoric" completely and devoted themselves to empire building. They built Cairo as capital in Egypt and their descendants continued to rule as Caliphs. The sixth caliph, Al-Hakim bi-Amr Allah, was known for "unpredictable commands" (destruction of churches, nocturnal ceasefires, liquidation of all dogs, prohibition of music) carried out with extreme violenceand occasionally rescinded with equal suddenness. His impulsiveness was believed by some to be divinely inspired and inspired the Druze religion,Filiu, Apocalypse in Islam , 2011: p. 52 adherents of whom believe he is in occultation and due to return as Mahdi on Judgment Day.

The dynasty ended when Salah-ud-Din Ayubi (also called Saladin) took over Egypt and ended the Fatimid state. He imprisoned the last Fatimid Caliph and his family in the Fatimid Palace for the rest of their lives.

Kadu ibn Mu'arik al-Mawati A young Kutama Berber, al-Mawati was proclaimed as the Mahdi by disillusioned adherents of al-Mahdi Billah, in the aftermath of the purge of Abu Abdallah al-Shi'i and anti-Kutama riots in the cities of Ifriqiya. The Fatimid heir-apparent, al-Qa'im was given command of an army sent against the rebels. On 21 June 912, the Fatimid army decisively defeated the rebels near Mila. The anti-Mahdi al-Mawati and the other rebel leaders were soon captured, and prominently featured in al-Qa'im's triumphal entry into Kairouan in autumn.

Abu'l-Fadl al-Isfahani Abu'l-Fadl al-Isfahani, also known as the Isfahani Mahdi, was a young Persian man who in 931 CE was declared to be "God incarnate" by Qarmatian leader of Bahrayn, Abu Tahir al-Jannabi. This new apocalyptic leader, however, caused great disruption by rejecting traditional aspects of Islam, and promoting ties to the old Persian religion of Zoroastrianism; "urging his followers" to denounce Abrahamic prophets and "celebrate fire" as Zoroastrians did. Abu Tahir disavowed him as an "imposter" and had him put to death.

Muhammad al-Mahdi Billah In the summer of 945, during the Kharijite revolt of Abu Yazid against the Fatimid Caliphate, a man claiming to be an Abbasid prince rose in revolt against Abu Yazid at Béja. He used a black banner and claimed to be the Mahdi, with the name Muhammad al-Mahi Billah. Very quickly he was arrested by Abu Yazid's son, Ayyub, and interrogated. After he was tested about his knowledge of Baghdad and proved to be unable to respond, he was crucified in front of the city gate.

Muhammad ibn al-Mustakfi

Muhammad ibn al-Mustakfi was the son and designated heir of the Abbasid caliph al-Mustakfi, he assumed the mantle of the Mahdi in a conspiracy to overthrow the Buyid Emirs and their puppet caliph, al-Muti.

Twelfth century Hassan II of Alamut In the late eleventh century, as the Fatimid dynasty relinquished any supranatural claims or interest in millenarianism, the Isma'ilis suffered another split. The head of the Fatimid army (Al-Afdal), sidelined the son designated heir (Abu Mansur Nizar) of the deceased caliph for a more compliant son-in-law. A revolt led by Nizar was crushed, but in Iran the commander of Isma'ili forces, Hasan-i-Sabbah, broke from the Fatimids in Cairo and commenced a reign of terror against both leaders of the Sunni Abbasids and the Fatimid court in Cairo from his citadel in Alamut.

In the middle of Ramadan in 559 AH (1164 CE), a successor of Hasan-i-Sabbah, Hassan II gathered his followers and announced to "jinn, men and angels" that the Hidden Imam had freed them "from the burden of the rules of Holy Law". With that, the assembled took part in a ritual violation of Sharia, a banquet with wine, in violation of the Ramadan fast, with their backs turned towards Medina. Hassan II explained that he had abrogated the exoteric practice of Sharia and stressed on the esoteric (batini) side of the laws. And "while outwardly he was known as the grandson of Buzurgumid", in his esoteric reality, Hasan claimed "he was the Imam of the Time" (the last Imam of Shia Islam). Observance of Islamic rites was punishable by the utmost severity. Resistance was nonetheless deep, and Hasan was stabbed to death by his own brother-in-law. Islamic law was reintroduced after the death of his son.Filiu, Apocalypse in Islam , 2011: p. 53

Ibn Tumart In Sunni Morocco, Muhammad ibn Abdullah ibn Tumart (c. 1078/1080 – c. 1130), sought to reform Almoravid decadence in the early 12th century. Rejected in Marrakech and other cities, he turned to his Masmuda tribe in the Atlas Mountains for support. Because of their emphasis on the unity of God, his followers were known as al-Muwahhidun ('Unitarians', in English; Almohads in the corrupted form).Filiu, Apocalypse in Islam , 2011: p. 59 Ibn Tumart rejected all other Islamic legal schools, and saw in the lax morality of the ruling Almorvid dynasty signs of that The Hour of Judgement was nigh.Filiu, Apocalypse in Islam , 2011: pp. 59–60

Although declared mahdi by his followers in 1121 CE,Filiu, Apocalypse in Islam , 2011: p. 60 and calling himself imam and masum (literally in Arabic: innocent or free of sin), Ibn Tumart consulted with a council of ten of his oldest disciples, and conform traditional Berber representative government, later added an assembly of fifty tribal leaders. The Almohad rebellion began in 1125 with attacks on Moroccan cities, including Sus and Marrakech.

His failure to capture Marrakech in 1130 "undermined his messianic pretentions to invulnerability", and he died shortly after he designated Abd al-Mu'min his successor with the title of Caliph. Abd al-Mu'min claimed universal leadership in Islamand placed members of his own family in power, converting the system into a traditional sultanate.

Fourteenth century

Musa Öljaitü had executed a Kurdish man named Musa who claimed to be the Mahdi of Shia Muslims.

Shia in Iran and Iraq With the Mongol invasion of the eastern Muslim world in the 13th century, many Muslims were killed, and Iran and Iraq came under Mongol control. By the early 14th century Shi'a in Iran and Iraq began "clandestine dissidence". For example, in Hilla, a center of Shi'i learning in central Iraq, each day from afternoon to evening prayer, 100 townsmen participated in a ritual appealing to the Mahdi to reappear. Drums were beaten, trumpets and bugles blown, a saddled horse for the Mahdi led to the sanctuary of the 'Master of the Hour' where the Shiʿa townsmen would cry: 'In the name of Allah, Master of the Hour, in the name of Allah, come, for disorder is rampant and iniquity rife! This is the moment for you to appear! Through you, Allah will make known the true [and separate] from the false!" Similar messianic events occurred in Iran.Filiu, Apocalypse in Islam , 2011: pp. 55–56 Fazlallah al-Astarbadi