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Ismāʿīlism (Arabic: الإسماعيليون al-Ismāʿīliyyūn; Persian: اسماعیلیان Esmāʿiliyān; Urdu: إسماعیلی Ismāʿīlī) is a branch of the Islamic faith. It is the second largest part of the Shī‘ah community, after the mainstream Twelvers (Ithnāʿashariyya). The Ismāʿīlī get their name from their acceptance of Ismāʿīl ibn Jaʿfar as the divinely appointed spiritual successor (Imām) to Jaʿfar aṣ-Ṣādiq, wherein they differ from the Twelvers, who accept Mūsà al-Kāżim, younger brother of Ismāʿīl, as the true Imām.
Mosque of al-Hakim, an Ismāʿīlī Shī‘ah Imām
Tracing its earliest theology to the lifetime of Muḥammad, Ismāʿīlism rose at one point to become the largest branch of Shī‘ism, climaxing as a political power with the Fatimid Empire in the tenth through twelfth centuries. In common with other Muslims, Ismailis believe in the oneness of God, as well as the closing of divine revelation with Muḥammad, whom they see as the final prophet and messenger of God to all humanity. The Ismāʿīlī and the Twelvers both accept the same initial A'immah from the descendants of Muḥammad through his daughter Fāṭimah az-Zahra and therefore share much of their early history. Both groups see the family of Muḥammad (Ahl al-Bayt) as divinely chosen, infallible (ismah), and guided by God to lead the Islamic community (Ummah).
After the death—or Occultation according to Seveners—of Muhammad ibn Ismail in the 8th century CE, the teachings of Ismailism further transformed into the belief system as it is known today, with an explicit concentration on the deeper, esoteric meaning (batin) of the Islamic religion. With the eventual development of Twelverism into the more literalistic (zahir) oriented Akhbari and later Usooli schools of thought, Shi'ism developed into two separate directions: the metaphorical Ismāʿīlī group focusing on the mystical path and nature of Allah, with the "Imām of the Time" representing the manifestation of truth and reality, with the more literalistic Twelver group focusing on divine law (sharia) and the deeds and sayings (sunnah) of Muhammad and the Twelve Imams who were guides and a light to God.
Though there are several paths (tariqah) within the Ismāʿīlīs, the term in today's vernacular generally refers to the Nizari path, which recognizes the Aga Khan as the 49th hereditary Imam and is the largest group among the Ismāʿīlīs. While some of the branches have extremely differing exterior practices, much of the spiritual theology has remained the same since the days of the faith's early Imāms. In recent centuries Ismāʿīlīs have largely been an Indo-Iranian community, but Ismāʿīlī are found in India, Pakistan, Syria, Saudi Arabia, Yemen, China, Jordan, Uzbekistan, Tajikistan, Afghanistan, East Africa, Syria, and South Africa, and have in recent years emigrated to Europe, Australia, New Zealand, and North America.
Succession to Muhammad
Ambigram depicting Muhammad and Ali written in a single word. The 180 degree inverted form shows both words.Ismailism shares its beginnings with other early Shī‘ah sects that emerged during the succession crisis that spread throughout the early Muslim community.
Ambigram depicting Muhammad and Ali written in a single word. The 180 degree inverted form shows both words.
From the beginning, the Shī‘ah asserted the right of ‘Alī, Muhammad's cousin, to have both political and spiritual control over the community. This also included his two sons, who were the grandsons of Muhammad through his daughter Fāṭimatu z-Zahrah.
The conflict remained relatively peaceful between the partisans of ‘Alī and those who asserted a semi-democratic system of electing caliphs, until the third of the Rashidun caliphs, Uthman was killed, and ‘Alī, with popular support, ascended to the caliphate. 
Soon after his ascendancy, Aisha, the third of the Prophet's wives, claimed along with Uthman's tribe, the Ummayads, that Ali should take Qisas (blood for blood) from the people responsible for Uthman's martyrdom. ‘Alī voted against it as he believed that situation at that time demanded a peaceful resolution of the matter. Both parties could rightfully defend their claims, but due to escalated misunderstandings, the Battle of the Camel was fought and both parties bore losses but soon reached an agreement.
Following this battle, Muawiya, the Umayyad governor of Syria, also staged a revolt under the same pretences. ‘Alī led his forces against Muawiya until the side of Muawiya held copies of the Quran against their spears and demanded that the issue be decided by Islam's holy book. ‘Alī accepted this, and an arbitration was done which ended in his favor. 
A group among Alī's army believed subjecting his legitimate authority to arbitration was tantamount to apostasy, and abandoned his forces. This group was known as the Kharijites, and ‘Alī wished to defeat their forces before they reached the cities where they would be able to blend in with the rest of the population. He was unable to do this, but nonetheless defeated their forces in the battles following afterward. 
Regardless of these defeats, the Kharijites survived and became a violently problematic group in Islamic history. After plotting an assassination against ‘Alī, Muawiya, and the arbitrator of their conflict, only ‘Alī was successfully assassinated in 661 CE, and the Imāmate passed on to his son Hasan and then later his son Husayn, or according to the Nizari Ismāʿīlī, straight to Husayn. However, the political caliphate was soon taken over by Muawiya who was the only leader in the empire at that time with an army large enough to seize control. 
Karbala and afterward
The Battle of Karbala
The Shrine of Imam Hussain ibn Ali in Karbala, IraqAfter the passing away of Hassan, Husayn and his family were increasingly worried about the religious and political persecution that was becoming commonplace under the reign of Muawiya's son, Yazid. Amidst this turmoil in 680 CE, Husayn along with the women and children of his family, upon receiving invitational letters and gesture of support by Kufis, wished to go to Kufa and confront Yazid as an intercessor on part of the citizens of the empire. However, he was stopped by Yazid's army in Karbala, during the month of Muharram. His family was starved and deprived of water and supplies, until eventually the army came in on the tenth day and killed Husayn and his companions, and enslaved the rest of the women and family, taking them to Kufa. 
This battle would become extremely important to the Shī‘ah psyche. The Twelvers, as well as Mustaali Ismāʿīlī still mourn this event during a holiday known as Ashura. The Nizari Ismāʿīlī however do not mourn this event because of the belief that the light of the Imām never dies but rather passes on to the succeeding Imām, making mourning arbitrary.
The beginnings of Ismāʿīlī Daʿwah
After being set free by the caliph Yazid, Zainab, the daughter of Fāṭimatu z-Zahra' and ‘Alī and the sister of Hassan and Husayn, started to spread the word of Karbala to the Muslim world, making speeches regarding the event. This was the first organized Daʿwah of the Shī‘ah community, which would later develop into an extremely spiritual institution for the Ismāʿīlīs.
After the poisoning of ‘Alī al-Sajjad by Hisham ibn Abd al-Malik in 713 CE, Shiism's first succession crisis rose with Zayd ibn ‘Alī's companions and the Zaydī Shī‘ah that claim Zayd ibn ‘Alī as the Imām, whilst the rest of the Shī‘ah maintained Muhammad al-Baqir as the Imām. The Zaidis argued that any sayed, descendant of Muhammad through Hassan or Husayn, who rebelled against tyranny and the injustice of his age, can be the Imām. The Zaidis created the first Shī‘ah states in Iran, Iraq and Yemen.
In contrast to his predecessors, Muhammad al-Baqir focused on academic Islamic scholarship in Medina, where he promulgated his teachings to many Muslims, both Shī‘ah and non-Shī‘ah, in an extremely organized form of Daʿwah.  In fact, the earliest text of the Ismaili school of thought is said to be the "Umm al-kitåb" (The Archetypal Book), a conversation between Muhammad al-Baqir and three of his disciples.
This tradition would pass on to his son, Ja'far al-Sadiq, who inherited the Imāmate on his father's death in 743. Ja'far al-Sadiq excelled in the scholarship of the day and had many pupils, including three of the four founders of the Sunni madhabs. 
However, following Jaffir's poisoning in 765, a fundamental split would occur in the community. Isma'il bin Jafar, who at one point seemed to be heir apparent, apparently predeceased his father in 755. While Twelvers either argue he was never heir apparent or that he truly predeceased his father hence Musa al-Kadhim was the true heir to the Imamate, Ismāʿīlīs argue that either the death was staged in order to draw harm away from al-Sadiq's successor or that his early death does not mean he was not an Imām, and rightfully the Imāmate would pass to his son, Muhammad ibn Ismail.
Ascension of the Dais
Shams Tabrizi in a circa 1503 copy of his disciple Rumi's poem, the "Diwan-e Shams-e Tabriz-i". Shams Tabrizi is believed to have been an Ismaili Dai and his relationship with Rumi a symbolic manifestation of the sacred relationship between the guide and the guided.For the Sevener Ismāʿīlī, the Imāmate ended with Isma'il ibn Ja'far, whose son Muhammad ibn Ismail was the expected Mahdi that Ja'far al-Sadiq had preached about. However, at this point the Ismāʿīlī Imāms according to the Nizari and Mustaali found areas where they would be able to be safe from the recently founded Abbasid Empire which had defeated and seized control from the Umayyads in 750 AD. 
Shams Tabrizi in a circa 1503 copy of his disciple Rumi's poem, the "Diwan-e Shams-e Tabriz-i". Shams Tabrizi is believed to have been an Ismaili Dai and his relationship with Rumi a symbolic manifestation of the sacred relationship between the guide and the guided
At this point, much of the Ismaili community believed that Muhammad ibn Ismail had gone into the Occultation and that he would one day return. With the status and location of the Imāms not known to the community, Ismailism began to propagate the faith through Dāʿiyyūn from its base in Syria. This was the start of the spiritual beginnings of the Daʿwah that would later blossom on the Mustaali branch of the faith, as well as play important parts in the other three branches. 
The Da'i was not a missionary in the typical sense, and he was responsible for both the conversion of his student as well as the mental and spiritual wellbeing. The Da'i was a guide and light to the Imām. The student and teacher relationship of the Da'i and his student was much like the one that would develop in Sufism. The student desired God, and the Da'i could bring him to God by making him recognize the stature and light of the Imām descended from the Imāms, which in turn descended from God. The Da'i was the path, and the Face of God which was a Qur'anic term the Ismāʿīlī took to represent the Imām, was the destination.
Shams Tabrizi and Rumi is a famous example of the importance between the guide and the guided, and Rumi dedicated much of his literature to Shams Tabrizi and his discovery of the truth.
While many of the Ismāʿīlī were content with the Dai teachings, a group that mingled Persian nationalism and Zoroastrianism with Ismāʿīlī teachings surfaced known as the Qarmatians. With their headquarters in Bahrain, they accepted a young Persian former prisoner by the name of Abu'l-Fadl al-Isfahani, who claimed to be the descendant of the Persian kings as their Mahdi, and rampaged across the Middle-East in the tenth century, climaxing their violent campaign with the stealing of the Black Stone from the Kaaba in Mecca in 930 under Abu Tahir Al-Jannabi. Following the arrival of the Mahdi they changed their qiblah from the Kaaba to the Zoroastrian-influenced fire. After their return of the Black Stone in 951 and a defeat by the Abbasids in 976 they slowly dwindled and no longer have any adherents.
The Fatimid Empire
The Fatimid Caliphate or al-Fātimiyyūn (Arabic الفاطميون) was an Arab Shi'a dynasty that ruled over varying areas of the Maghreb, Egypt, Sicily, Malta and the Levant from 5 January 909 to 1171. The caliphate was ruled by the Fatimids, who established the Egyptian city of Cairo as their capital. The term Fatimite is sometimes used to refer to the citizens of this caliphate. The ruling elite of the state belonged to the Ismaili branch of Shi'ism. The leaders of the dynasty were also Shia Ismaili Imams, hence, they had a religious significance to Ismaili Muslims. They are also part of the chain of holders of the office of Caliph, as recognized by most Muslims. Therefore, this constitutes a rare period in history in which some form of the Shia Imamate and the Caliphate were united to any degree, excepting the Caliphate of Ali himself. It should be noted here, however, that these Ismaili Imams are not considered rightful Imams (nor seen to possess any other spiritual or religious significance) by the overwhelming majority of Shias known as Twelvers. Thus, most Shias would not consider the Fatimid period of rule as a unification of Caliphate and Imamate.
With exceptions, the Fatimids were reputed to exercise a degree of religious tolerance towards non-Ismaili sects of Islam as well as towards Jews, Maltese Christians and Coptic Christians.
Rise of the Fatimids
The Fatimids had their origins in Ifriqiya (modern-day Tunisia and eastern Algeria). The dynasty was founded in 909 by ˤAbdullāh al-Mahdī Billah, who legitimised his claim through descent from Muhammad by way of his daughter Fātima as-Zahra and her husband ˤAlī ibn-Abī-Tālib, the first Shīˤa Imām, hence the name al-Fātimiyyūn "Fatimid".
Abdullāh al-Mahdi's control soon extended over all of central Maghreb, an area consisting of the modern countries of Morocco, Algeria, Tunisia and Libya, which he ruled from Mahdia, his newly-built capital in Tunisia.
The Fatimids entered Egypt in the late 900s, conquering the Ikhshidid dynasty and founding a new capital at al-Qāhira (Cairo) in 969. The name was a reference to the planet Mars, "The Subduer", which was prominent in the sky at the moment that city construction started. Cairo was intended as a royal enclosure for the Fatimid caliph and his army, though the actual administrative and economic capital of Egypt was in cities such as Fustat until 1169. After Egypt, the Fatimids continued to conquer the surrounding areas until they ruled from Tunisia to Syria and even crossed over into Sicily and southern Italy.
Under the Fatimids, Egypt became the center of an empire that included at its peak North Africa, Sicily, Palestine, Lebanon, Syria, the Red Sea coast of Africa, Yemen and the Hejaz. Egypt flourished, and the Fatimids developed an extensive trade network in both the Mediterranean and the Indian Ocean. Their trade and diplomatic ties extended all the way to China and its Song Dynasty, which eventually determined the economic course of Egypt during the High Middle Ages.
Unlike other governments in the area, Fatimid advancement in state offices was based more on merit than on heredity. Members of other branches of Islam, like the Sunnis, were just as likely to be appointed to government posts as Shiites. Tolerance was extended even to non-Muslims such as Christians and Jews, who occupied high levels in government based on ability. There were, however, exceptions to this general attitude of tolerance, most notably Al-Hakim bi-Amr Allah.
The Fatimids were also known to some extent for their arts. A type of ceramic, lustreware, was prevalent during the Fatimid period. Glassware and metalworking was also popular. Many traces of Fatimid architecture exist in Cairo today, like the Al Azhair University and the Al Hakim mosque.
The Fatimid palace was two parts. it used to be in the Khan el-Khalili area at Bin El-Quasryn street.
Decay and fall
In the 1040s, the Zirids (governors of North Africa under the Fatimids) declared their independence from the Fatimids and their conversion to Sunni Islam, which led to the devastating Banū Hilal invasions. After about 1070, the Fatimid hold on the Levant coast and parts of Syria was challenged first by Turkish invasions, then the Crusades, so that Fatimid territory shrank until it consisted only of Egypt.
After the decay of the Fatimid political system in the 1160s, the Zengid ruler Nūr ad-Dīn had his general Shirkuh, seize Egypt from the vizier Shawar in 1169. Shirkuh died two months after taking power, and the rule went to his nephew, Saladin. This began the Ayyubid Dynasty.
1.Abū Muḥammad ˤAbdu l-Lāh (ˤUbaydu l-Lāh) al-Mahdī bi'llāh (909-934) founder Fatimid dynasty
2.Abū l-Qāsim Muḥammad al-Qā'im bi-Amr Allāh (934-946)
3.Abū Ṭāhir Ismā'il al-Manṣūr bi-llāh (946-953)
4.Abū Tamīm Ma'add al-Mu'izz li-Dīn Allāh (953-975) Egypt is conquered during his reign
5.Abū Manṣūr Nizār al-'Azīz bi-llāh (975-996)
6.Abū 'Alī al-Manṣūr al-Ḥākim bi-Amr Allāh (996-1021) Founder of the Druze religion
7.Abū'l-Ḥasan 'Alī al-Ẓāhir li-I'zāz Dīn Allāh (1021-1036)
8.Abū Tamīm Ma'add al-Mustanṣir bi-llāh (1036-1094)
9.al-Musta'lī bi-llāh (1094-1101) Quarrels over his succession led to the Nizari split.
10.al-Āmir bi-Aḥkām Allāh (1101-1130) The Fatimid rulers of Egypt after him are not recognized as Imams by Mustaali Taiyabi Ismailis.
11.'Abd al-Majīd al-Ḥāfiẓ (1130-1149)
1. Wintle, Justin (May 2003). History of Islam. London: Rough Guides Ltd. pp. 136–7. ISBN 184353018X.
2. Beeson, Irene (September/October 1969). "Cairo, a Millennial". Saudi Aramco World: 24, 26–30. http://www.saudiaramcoworld.com/issue/1 ... ennial.htm. Retrieved 2007-08-09.
3. Amin Maalouf (1984). The Crusades Through Arab Eyes. Al Saqi Books. pp. 160–170. ISBN 0-8052-0898-4.
Rise of the Fatimid Empire
The political asceticism practiced by the Imāms during the period after Muhammad ibn Ismail was to be short lived and finally concluded with the Imāmate of Ubayd Allah al-Mahdi Billah, who was born in 873. After decades of Ismaili believing that Muhammad ibn Ismail was in the Occultation and would return to bring an age of justice, al-Mahdi taught that the Imāms had not been literally secluded, but rather had remained hidden to protect themselves and had been organizing the Da'i, and even acted as Da'i themselves. He taught that during the supposed Occultation of Muhammad ibn Ismail, many of Muhammad ibn Ismail's descendants lived as Imāms secluded from the community, guiding them through the Da'i at times even taking the guise of Da'i.
After raising an army and successfully defeating the Alghabids in North Africa and a number of other victories, al-Mahdi Billah successfully established a Shi'ah political state ruled by the Imāmate in 910 AD.  This was the only time in history where the Shi'a Imamate and Caliphate were united after the first Imam, Ali ibn Abu Talib.
In parallel with the dynasty's claim of descent from ‘Alī and Fāṭimatu z-Zahrah, the empire was named “Fatimid.” However, this was not without controversy and with the extent that the Ismāʿīlī Daʿwah had spread, the Abbasid caliphate assigned Sunni and Twelver scholars with the assignment to disprove the lineage of the new dynasty. This became known as the Baghdad Manifesto, and it traces the lineage of the Fatimid dynasty to a Jewish blacksmith. Its authenticity has been both questioned and supported by many Islamic scholars.
The Middle-East under Fatimid rule
The Fatimid Empire expanded quickly under the subsequent Imāms. Under the Fatimids, Egypt became the center of an empire that included at its peak North Africa, Sicily, Palestine, Syria, the Red Sea coast of Africa, Yemen and the Hejaz. Under the Fatimids, Egypt flourished and developed an extensive trade network in both the Mediterranean and the Indian Ocean, which eventually determined the economic course of Egypt during the High Middle Ages.
The Fatimid Empire at its peak.
The Fatimids promoted two ideas that were radical for that time. The first was promotion by merit rather than genealogy. The second was religious toleration, under which both Jews and Coptic Christians flourished.
Also during this period the three contemporary branches of Ismailism formed. The first branch (Druze) occurred with the Imām Al-Hakim bi-Amr Allah. Born in 985, he ascended as ruler at the age of eleven and was feared for his eccentricity and believed insanity. The typical religiously tolerant Fatimid Empire saw much persecution under his reign. When in 1021 his mule returned without him, soaked in blood, a religious group that was even forming in his lifetime broke off from mainstream Ismailism and refused to acknowledge his successor. Later to be known as the Druze, they believe Al-Hakim to be the manifestation of God and the prophecized Mahdi, who would one day return and bring justice to the world.  The faith further split from Ismailism as it developed very unique doctrines which often classes it separately from both Ismailism and Islam.
The second split occurred following the death of Ma'ad al-Mustansir Billah in 1094. His rule was the longest of any caliph in both the Fatimid and other Islamic empires. Upon his passing away his sons, the older Nizar and the younger Al-Musta'li fought for political and spiritual control of the dynasty. Nizar was defeated and jailed, but according to Nizari tradition his son escaped to Alamut where the Iranian Ismāʿīlī had accepted his claim. 
The Mustaali line split again between the Taiyabi and the Hafizi, the former claiming that the 21st Imām and son of Al-Amir went into occultation and appointed a Dāʿī al-Muṭlaq to guide the community, in a similar manner as the Ismāʿīlī had lived after the death of Muhammad ibn Ismail. The latter claimed that the ruling Fatimid caliph was the Imām.
Decline of the empire
In the 1040s, the Zirids (governors of North Africa under the Fatimids) declared their independence from the Fatimids and their conversion to "orthodox" Sunni Islam, which led to the devastating Banu Hilal invasions. After about 1070, the Fatimid hold on the Levant coast and parts of Syria was challenged by first Turkish invasions, then the Crusades, so that Fatimid territory shrunk until it consisted only of Egypt.
After the decay of the Fatimid political system in the 1160s, the Zengid ruler Nūr ad-Dīn had his general, Saladin, seize Egypt in 1169, forming the Sunni Ayyubid Dynasty. This signaled the end of the Hafizi Mustaali branch of Ismailism as well as the Fatimid Empire.
Alamūt (Persian language Persian: الموت "Eagle taught" or "Eagle's Nest") was once a mountain fortress located in the central Alborz Mountains south of the Caspian Sea close to Gazor Khan near Qazvin Province, about 100 km from present-day Tehran in Iran. Only ruins remain of this fortress today.
View of top.
Hashshashin fortress of Alamut.
Scaffolding by Iran's Cultural Heritage Organization.
Alamut lies on the peak known as Alah Amut. Among suggested etymologies are "Eagle's Nest" (according to Sar Guzasht-i Sayyidna) and "Eagle's Teaching" (according to "Kamil fit-Tarikh" of Ibn Athir).
According to Hamdollah Mostowfi, the first fortress was built in 840 at an elevation of 2100m. It was built in a way that had only one passable artificial entrance that wound its way around the cliff face (the one natural approach, a steep gravel slope, was too dangerous to use); thus making conquering the fortress extremely difficult. The fort had an unusual system of water supply. The top was extremely narrow and long — perhaps 400 meters long, and no more than 30 meters wide in any place and usually less.
In 1090 the fortress was infiltrated and occupied by the powerful Hashshashins, a faction of Nizāri Ismā‘ilī Shī‘a Islam known to the West as "the Assassins", and was then fabled for its gardens and libraries. The ruins of 23 other fortresses remain in the vicinity.
The fortress was destroyed on December 15, 1256 by Hulagu Khan as part of the Mongol offensive on Islamic southwest Asia. The fortress itself was impregnable, but Ruknud-Dīn Khurshāh surrendered it without a real fight, in the vain hope that Hulagu would be merciful.
In 2004, an earthquake further damaged the already crumbling walls of the fort.
Very early in the empire's life, the Fatimids sought to spread the Ismāʿīlī faith which in turn would spread loyalties to the Imāmate in Egypt. One of their earliest attempts would be taken by a Dai by the name of Hassan-i-Sabbah.
Artistic Rendering of Hassan-i-Sabbah
Hassan-i-Sabbah was born into a Twelver family living in the scholarly city of Qom in 1056 AD. His family later relocated to the city of Tehran which was an area with an extremely active Ismāʿīlī Daʿwah. He immersed himself in Ismāʿīlī thought, however he did not choose to convert until he was overcome with an almost fatal illness, where he finally feared dying without knowing the Imām of his time.
Afterwards, Hassan-i-Sabbah became one of the most influential Dais in Ismāʿīlī history, and would be important to the survival of the Nizari branch of Ismailism, which today is its largest branch.
Legend holds that he met with Imām Ma'ad al-Mustansir Billah and asked him who his successor would be, to which he responded, his eldest son Nizar.
Hassan-i-Sabbah would continue his Dai activities and they would climax with his taking of Alamut. Taking two years, he first converted most of the surrounding villages to Ismailism. Afterwards, he converted most of the staff to Ismailism and then took over the fortress, and presented the current leader with payment for the fortress. With no choice, the leader abdicated and Hassan-i-Sabbah turned Alamut into an outpost of Fatimid rule within Abbasid territory.
Surrounded by the Abbasids and other hostile powers, and low in numbers, Hassan-i-Sabbah derived a way to attack the Ismāʿīlī enemies with a small loss and number. Using the method of assassination, from which the English word is derived from Hashashin, he ordered the killing of Sunni scholars and politicians that threatened the Ismāʿīlīs. Knives and daggers were used. Sometimes, in warning, a knife would be put into the pillow of the enemy and often they understood the message. 
However, when an assassination was actually made the Hashashin would not be allowed to run away, but rather to strike further fear in the enemy by showing no emotion, they would stand there. This further increased the reputation of the Hashashin in the Sunni world. 
Amin Maalouf, in his novel Samarkand, disputes the origin of the word assassin. According to him it is not derived from the name of the drug hashish which Westerners used to believe the sect took. Instead he proposes this story was fabricated by Orientalists to explain how faithfully the Ismāʿīlīs would carry out these suicide-assassinations without fearing death. Maalouf suggests that the term is derived from the word assaas (foundation), and Assassiyoon, meaning "those faithful to the foundation." 
Threshold of the Imāmate
View of Alamut besieged.After the imprisonment of Nizar by his younger brother Mustaal, it is claimed Nizar's son al-Hādī survived and fled to Alamut. He was offered a safe place in Alamut where Hassan-i-Sabbah welcomed him. However, it is believed this was not announced to the public and the lineage was hidden until a few Imāms later. 
View of Alamut besieged.
It was announced with the advent of Imām Hassan II, who some historians believe to be a descendant of the leaders of Alamut and not of Nizar. In a show of his Imāmate and to emphasize the interior meaning (the batin) over the exterior meaning (the zahir) he prayed with his back to Mecca, as did the rest of the congregation which prayed behind him, and ordered the community to break their Ramadan fasting with a feast at noon. He made a speech saying he was in communication with the Imām, which many of the Ismāʿīlīs understood to mean he was the Imām himself. 
Afterwards his descendants would rule as the Imāms at Alamut until its destruction by the Mongols.
Destruction by the Mongols
The stronghold at Alamut, though it had warded off the Sunni attempts to take it several times, including one by Saladin, would soon meet with destruction. By 1206, Genghis Khan had managed to unite many of the once antagonistic Mongol tribes into a unified force. Using many new and unique military techniques, Genghis Khan led the Mongols across Central Asia into the Middle-East where they won a series of tactical military victories.
A grandson of Genghis Khan, Hulagu Khan, led the devastating attack on Alamut in 1256, only a short time before he would sack the Abbasid caliphate in Baghdad in 1258. As he would later do to the House of Wisdom in Baghdad, he destroyed all Ismāʿīlī religious texts. The Imāmate that was located in Alamut along with its few followers were forced to flee and take refuge elsewhere.
After the fall of the Fatimid Empire and its bases in Iran and Syria, the three currently living branches of Ismāʿīlī generally developed geographically isolated from each other, with the exception of Syria (which has both Druze and Nizari) and Pakistan and rest of South Asia (which had both Mustaali and Nizari).
The Nizari kept large populations in Syria, Uzbekistan, Tajikistan, Afghanistan, Pakistan, India, and has smaller populations in China and Iran. This community is the only one with a living Imām, who is titled today as the Aga Khan.
The Druze mainly settled in Syria and Lebanon, and developed a community based upon the principles of reincarnation through their own descendants. Their leadership is based through community scholars, who are the only individuals allowed to read their holy texts. It is controversial whether this group falls under the classification of Ismāʿīlīsm or Islam because of their unique beliefs.
The Mustaali split several times over disputes regarding who was the rightful Dāʿī al-Muṭlaq, the leader of the community within The Occultation. The Sulaimani Bohra are mostly concentrated in Yemen and Saudi Arabia with some communities in the Indian Subcontinent. The Dawoodi Bohra and Alavi Bohra are mostly exclusive to the Indian Subcontinent. Other groups include Atba-i-Malak and Hebtiahs Bohra. Mustaali beliefs and practices, unlike those of the Nizari and Druze, are generally compatible with mainstream Islam, representing a continuation of Fatimid tradition and fiqh'.
View on the Qur'an
Ismaili believe the Qur'an has two layers of meaning, the zahir meaning apparent, and the batin, meaning hidden.The Ismāʿīlīs understand the Qur'an to have several layers of meaning, but generally divide those types of meanings into two: the apparent (zahir) meaning and the hidden (batin) meaning. While a believer can understand the batin meaning to some extent, the ultimate interpretation lies in the office of the Imāmate. The Imām's farmans (teachings) are binding upon the community. In this way, the Ismāʿīlī community can adapt to new times and new places.
The Ginans are Nizari Ismā‘īlī religious texts. They are written in the form of poetry by Pirs to interpret the meanings of Qur’anic ayat into the languages of the Indian subcontinent, especially Gujarati and Urdu. In comparison to Ginans, Ismāʿīlīs of other origins, such as Persians, Arabs, and Central Asians have qasidas (Arabic: قصيدة) written by missionaries. See Works of Pir Sadardin
Reincarnation exists in the Druze branch of Ismailism. The Druze believe that members of their community can only be reincarnated within the community. It is also known that Druze believe in five cosmic principles, represented by the five colored Druze star: intelligence/reason (green), soul (red), word (yellow), precedent (blue), and immanence (white). These virtues take the shape of five different spirits which, until recently, have been continuously reincarnated on Earth as prophets and philosophers including Adam, the ancient Greek mathematician and astronomer Pythagoras, and the ancient Pharaoh of Egypt Akhenaten, and many others. The Druze believe that, in every time period, these five principles were personified in five different people who came down together to Earth to teach humans the true path to God and nirvana, but that with them came five other individuals who would lead people away from the right path into "darkness".
Ismāʿīlīs believe numbers have religious meanings. The number seven plays a general role in the theology of the Ismā'īliyya, including mystical speculations that there are seven heavens, seven continents, seven orifices in the skull, seven days in a week, and so forth.
In Nizari Ismailism, the Imām is seen through the Qur'anic phrase, “The Face of God.” The Imām is truth and reality itself, and hence he is their path of salvation to God. 
Sevener Ismāʿīlī doctrine holds that divine revelation had been given in six periods (daur) entrusted to six prophets, who they also call Natiq (Speaker), who were commissioned to preach a religion of law to their respective communities.
Whereas the Natiq was concerned with the rites and outward shape of religion, the inner meaning is entrusted to a Wasi (Representative). The Wasi would know the secret meaning of all rites and rules and would reveal them to a small circles of initiates.
The Natiq and the Wasi are in turn succeeded by a line of seven Imāms, who would guard what they received. The seventh and last Imām in any period would in turn be the Natiq of the next period. The last Imām of the sixth period however would not bring about a new religion of law but supersede all previous religions, abrogate the law and introduce din Adama al-awwal ("the original religion of Adam") practised by Adam and the Angels in paradise before the fall, which would be without cult or law but consist merely in all creatures praising the creator and recognizing his unity. This final stage was called Qiyamah.