Hassan as-Sabbah was born in 1044 in Qum, in Iran, a few kilometres from the city of Ravy, which would become Tehran. An intelligence greater and eager for knowledge, he threw himself at heart lost in reading at the expense of his father who wanted to make a cloth merchant.Sent in a madrasa in Ravy, where he made the acquaintance of Omar Khayyam, the future Persian poet, who dedicated him a great friendship, and Abd el-Kassim, who will become the Great Vizier Nizam el-Mulk, who him will testify a great enmity. In Ravy, he followed studies to become Imam before be convinced by a Daï, a preacher, that the Ismaili heresy was the one who held the truth. From then on, he devoted his life to defend the Ismaili doctrine.Become an adult, he arrived in Isfahan at the request of his friend Omar Khayyam, science at the Court of the Sultan Malik Shah, putting his knowledge at its service before joining the Kings Council. The extent of its competence will increase the jealousy of the Great Vizier, who will see compete to attract the protection of the monarch. Nizam el-Mulk will have the last word and Hassan will have to flee the capital to escape death. Therefore,he consigns him an eternal hatred.Hassan as-Sabbah through Persia to escape his pursuers and arrive in India, in Kabul, where he discovered that the Hashish provokes those who consume. This discovery will give him the idea to exploit the virtues of this plant to make discover the notion of paradise to his supporters.After some years of wandering, Hassan went to Egypt where there was the Fatimid Caliph al-Mustansir Billah in applying the doctrine Shiite Ismaili. He will be hosted by a master before being caught in the torments of the estate, after the Caliph falls ill, between supporters of the prince Nizar, elder and heir designate, which took the party, and those of the prince Ahmed, youngest son, supported by the Great Vizier Badr al-Jamali. This antagonism between the two sides will be him arrested and imprisoned. He must escape to a twist of fate where some saw the intervention of God.Hassan as-Sabbah won Syria where he was greeted by the Ismailis. From there, he won Persia where he began seeking the castle he saw non-stop in his dreams. He wandered for years before discovering Alamut, “The Nest of the Eagle" in the mountains of Elbrus in North of the Iran. When he will gain control of the fortress, he made a refuge where he gathered his supporters and led his war against the Seljuk Turks, in general, and Nizam el-Mulk, in particular.The hatred that drives will see compete by combatants interposed until the day where one of its Fedais, member of his elite unit, formed to carry out special missions after "visiting paradise" in consuming Hashish, kill the Great Vizier Nizam el-Mulk. Thirty-five days after him, it will be the Sultan Malik Shah, who will be assassinated by two other Fedais.Therefore, the Seljuks led a fight without end to destroy the Ismaili community in besieging their castles and destroying and looting their cities. But the actions of the Fedais began a term in these battles by assassinating their opponents, that they are Qadis, judges, Imams, viziers, Great viziers and same Sultans.The community of the Ismailis, their detractors will call the sect of the Hashashin, Hashish consumers, which will give the word Assassin, fought to be able to worship in peace for several decades in the East against those who prevented them.