Hasan Ali, or Abu'l Hasan, surnamed Zikrihi's Salam (peace be on his mention) was born in Alamut. He is reported to have born in 539/1145, but according to another tradition, he was born in 536/1142.
His other titles were Maliku'r riqab (Lord of the slaves), Maliku'l qulub (Lord of the hearts), Malik as-Salam (Lord of peace), Hasan-i Kabir (Hasan, the great) and Qaim al-Qiyama (Lord of resurrection). Among the Iranian sources, he is widely known as Hasan Ala Zikrihi's Salam, and in the Syrian sources, he is called Aqa dhikrihi al-Salam. Mustapha Qazwini writes in "Tarikh-i Guzida" (ed. by Nicholson, Leiden, 1910, p. 523) that, "He was also known as Kura Kiya (Lord of the villages) in Qazwin, a fact which suggests that the people of Qazwin were especially acquainted with him."
The historians call him Hasan II with a view to count Hasan bin Sabbah as Hasan I in the series of Alamut's rulers, while other make his father, al-Kahir as Hasan I and Hasan II to him in the list of Alamut's Imams.
To understand the Muslim world, we must cast a rapid glance over contemporary period that the Abbasid caliph Mustanjid (d. 566/1170) was ruling in Baghdad at that time. The Seljuq sultan Arslan (d. 571/1176) was reigning in Iran. In Egypt, the last ruler of the Fatimid empire was al-Adid (d. 567/1171). The Muslim rules were submerging in declination, therefore, none among them had a courage to attack on Alamut.
According to "Religion, Learning and Science in the Abbasid Period" (ed. by Young, Latham and Ser Jeuit, London, 1990, p. 245), "Al- Hasan bin Sabbah's two dai successors were followed at Alamut by the Imam al-Hasan bin Qahir bin Muhtadi bin Hadi bin Nizar."
Ata Malik Juvaini (1126-1283) compiled "Tarikh-i Jhangusha" in 658/ 1260 which stands an early source material. He and later historians are responsible to distort the historical fact and produced an incredible image of the Ismaili history and doctrines. Juvaini's work, to quote W. Barthold in "Turkestan down to the Mongol Invasion" (London, 1928, p. 40), "has not yet been valued at his deserts." Barthold further writes, "Juvaini is not completely master of his materials; in his narrative there are sometimes flagrant contradictions to be found." (Ibid.) According to "Historians of the Middle East" (London, 1962, p. 136), "Juvaini's sources appear to have been purely oral." Sir John Glubb also writes in "The Lost Centuries" (London, 1967, p. 271) that, "Juvaini served under Halagu in Persia and was thus perhaps obliged to flatter him." Henry H. Howorth remarks in his "History of the Mongols" (London, 1876, 1st vol., pp.20-21) that, "His position prevented Juvaini from being anything but a panegyrist of the Mongols, whose conquests he excuses, and whose western campaign he argues was providentially arranged, so that by their means the religion of Islam might be widely disseminated." D'Ohsson was the first European to have examined the work of Juvaini critically, and accused him of extravagant flattery of the Mongols, vide "Histoire des Mongols" (Amsterdam, 1834, 1st vol., p. 20). In the words of Marshall Hodgson, "Juwayni read records in the Alamut Nizari library after its capture, before ordering its destruction. He wrote an account based on these sources, but altered in form to suit an anti-Nizari taste, and decked with curses." (op. cit., p. 26). It is therefore, difficult to determine any exactitude in the hyperbolic words of Juvaini as Marshall Hodgson also regards him, "a special enemy of the Ismailis." (op. cit. p. 274)
Juvaini emphasised in placing Imam Hasan Ala Zikrihi's Salam (Hasan II) as the son of Muhammad bin Kiya Buzrug, in a doubtful manner. His objective was to connect the lineage of the Imams with Muhammad bin Kiya. Juvaini and the later historians however had to admit that when Imam Hasan II made his appearance before his followers, thronged at Alamut, none opposed or considered him as the son of Muhammad bin Kiya. If there had been a little doubt, it is possible that they, or a faction must have opposed without taking oath of allegiance, as it is a corner-stone of the Ismaili doctrines that an Imam must be a son of the Imam. No person can dare or venture on that occasion to claim for Imamate, and if it was true, it must have been claimed in other region, and not inside the castle, where his life was most possibly fraught in danger.
According to "Dabistan al-Mazahib" (comp. in 1653, p. 237), "Only the enemies of Hasan Ala Zikrihi's Salam considered him the son of Muhammad bin Kiya Buzrug." Dr. Nassih Ahmed Mirza writes in "Syrian Ismailis at the time of the Crusades" (an unpublished dissertation, University of Durham, 1963, p. 191) that, "During his (Hasan II) reign, his enemies spread false rumours that he was not a genuine descendant of Nizar, but these slanders were received by his followers with disgust and dissatisfaction. As for the Imam himself, he paid no attention to such slanders, but continued to send orders to his governors and dais under his seal and signature which include his family trees, thus ignoring the propaganda of his calumniators."
Juvaini and other attempted to equate Imam Hasan II with Hasan, the son of Muhammad bin Kiya, making them one character, and tried to brush aside the historicity of Hasan II. In sum, Juvaini emphasised from beginning to end that Hasan, the son of Muhammad bin Kiya had impersonated as an Imam. The undeniable thing in the face of facts however reveals that these two persons, each known as Hasan at one time were two separate characters. Dr. Mustapha Ghaleb in "The Ismailis of Syria" (Beirut, 1970, pp. 73-74) has appended an important letter of Imam Hasan II, which had been circulated among the Ismailis in 558/1163. This letter itself asserts that both Hasan II and Hasan, the son of Muhammad bin Kiya were two separate persons at one time. It reads:- "Our deputy, al-Hasan bin Muhammad bin Kiya Buzrug is our dai and hujjat. All those who follow our doctrine have to obey him in the religious and civic affairs, and to execute his orders and consider his speeches as ours. We hope that they will not disobey; but be abided by it and act as if it was issued by us."
It must, of course, be borne in mind that there had been three hidden Imams (al-a'imma al-masturin) between al-Nizar and Hasan II during the period of dawr-i satr in Alamut, whose historicity had been also stamped in the work of Juvaini.
One important Syrian manuscript has been discovered, whose author and date of writing are unknown. The copyist gives his date of writing in 1263/1846. According to Dr. Nassih Ahmed Mirza, "The only clues that can be obtained are from the literary style and from the biographical works of the Imams. These suggest that the date (of the above Ms.) may be taken as sometimes during the second half of the 14th century A.D." (p.176). On pp. 249-250, the author of this Ms. gives the genealogy of Imam Hasan II as "Hasan Ala Zikrihi's Salam bin al-Qahir bin al-Mohtadi bin al-Hadi bin al-Nizar." Dr. Nassih Ahmed Mirza concludes his remarks that, "This is the only available Syrian manuscript which gives the same genealogical tree of the Nizari Imams as the one accepted by the modern Aga Khani Ismailis." (p.176).
Muhibb Ali Qunduzi compiled his "Irshadu't-talibin di dhikr A'immati'l-Ismailiyya" in 930/1523 and asserts that there were three hidden Imams between Hasan II and al-Nizar, viz. Hadi, Mohtadi and Qahir. Ghiyasu-din bin Humami'd-din Khondamir (d.941/1534) compiled "Habibu's-Siyar" (Bombay, 1857, 3rd vol., p. 77) in 935/1528, also admits that there were three generations between Hasan II and al- Nizar, i.e., Hadi, Mohtadi and Qahir. Abu Ishaq Kohistani, who died in the beginning of the 16th century also writes in "Haft Bab" (tr. by W. Ivanow, Bombay, 1959, p. 23) that, "Mawlana Mustansir was succeeded by Mawlana Nizar, Mawlana Hadi, Mawlana Mohtadi, Mawlana Qahir and Mawlana Hasan Ala Zikrihi's Salam."
Among the modern scholars, John Norman Hollister writes in "The Shia of India" (London, 1953, p. 314) that, "Nizarin records are scarce having been largely destroyed in the period of Hasan's grandson, or by Halagu Khan when the fortress of Alamut was taken, but the traditions of the sect indicate that there were three Imams during this period: Hadi, son of Nizar, Mahdi or Muhtadi, and Qahir." According to Margoliouth in "Encyclopaedia of Religion and Ethics" (Edinburg, 1974, 2nd vol., p. 141) that, "Hasan II though supposed to be the son of the governor of Alamut, was in reality the heir of this Nizar." W. Ivanow also states in "Ismailitica" (Calcutta, 1922, p. 71) that, "The version that Hasan was a lineal descendant of Kiya Buzrug Ummid naturally cannot be of sectarian origin, even should it be true."