As organised by Hasan-i-Sabbah the Assassins appear in six grades. The highest of these was filled by the “Chief Daʿi” who recognised the Imam alone as superior on earth. So long as Mustansir lived he was regarded as the true Imam; after his death Nizar was his successor, and later on we find the Chief Daʿi claiming descent from Nizar, but this was as yet in the future. It was the same development as that which we have already observed in the history of the Shiʿite sect founded by ʿAbdullah b. Maymun. Amongst outsiders the Chief Daʿi commonly went by the name of “Sheikh of the mountain,” _i.e._, of the mountain stronghold of Alamut which formed the headquarters of the sect, and this is reproduced as “the old man of the mountain” in the records of the Crusaders. Under the Chief Daʿi were the “Senior Missionaries” (daʿi-i-kabir), each supervising a diocese or _bahr_ (“sea”), and under these were the ordinary missionaries. Thus far the organization merely reproduced that already prevalent in the Ismaʿilian propaganda. Beneath the missionaries were the ordinary members in two main grades known respectively as “companions” (rafiq) and “adherents” (lasiq), the former more fully initiated in the batimite or allegorical interpretations of doctrine than the latter. The sixth grade, theoretically the lowest, was peculiar to the Assassin sect, and consisted of “devoted ones” (fidaʿi) who do not seem to have been initiated, but were bound to a blind and unquestioning obedience which has its parallel in the discipline of the various darwish orders, but was here carried to exceptional extremes. These _fidaʿis_ were carefully trained and were especially practised in the use of various forms of disguise, after all only a more perfect refinement of the methods originally evolved by the Hashimite missionaries; but these were not disguised for the purpose of acting more efficiently as missionaries and for penetrating different communities as teachers, but solely for the purpose of carrying out the specific orders of the Chief Daʿi, and thus formed a most formidable branch of what soon became an exceptionally powerful secret society. In many cases the acts entrusted to the _fidaʿis_ were acts of murder, and it is from this that the name of “assassin” has received its peculiar meaning in most of the languages of Western Europe. The _fidaʿi_, trained to the use of disguise, sometimes as a servant, or as a merchant, or darwish, or as a Christian monk, was able to penetrate into almost any society and to strike down suddenly the victim marked out; and counted it a triumphant success if this act involved his own death as well. A deliberate effort was made to surround the sect with an atmosphere of terror; a Muslim prince would be struck down whilst he was acting as leader at prayer, or a Crusading knight as he was attending high mass at the head of his troops, or if there was not actual murder, a leader might wake up in his tent to find a message