Although the affairs of kingdoms and of nations, like the revolutions of day and night, are generally repeated in countless and continued successions, we, nevertheless, in our survey of the destinies of the human race, encounter single great and important events, which, fertilizing like springs, or devastating like volcanoes, interrupt the uniform wilderness of history. The more flowery the strand,—the more desolating the lava,—the rarer and more worthy objects do they become to the curiosity of travellers, and the narratives of their guides. The incredible, which has never been witnessed, but is nevertheless true, affords the richest materials for historical composition, providing the sources be authentic and accessible. Of all events, the account of which, since history has been written, has descended to us, one of the most singular and wonderful is the establishment of the dominion of the Assassins—that _imperium in imperio_, which, by blind subjection, shook despotism to its foundations; that union of impostors and dupes which, under the mask of a more austere creed and severer morals, undermined all religion and morality; that order of murderers, beneath whose daggers the lords of nations fell; all powerful, because, for the space of three centuries, they were universally dreaded, until the den of ruffians fell with the khaliphate, to whom, as the centre of spiritual and temporal power, it had at the outset sworn destruction, and by whose ruins it was itself overwhelmed. The history of this empire of conspirators is solitary, and without parallel; compared to it, all earlier and later secret combinations and predatory states are crude attempts or unsuccessful imitations. Notwithstanding the wide space, to the extremest east and west, over which the name of Assassins (of whose origin more hereafter) has spread, and that in all the European languages it has obtained and preserved the same meaning as the word _murderer_, little has hitherto been made known, in consecutive order, or satisfactory representation, of their achievements and fortunes, of their religious or civil codes. What the Byzantines, the Crusaders, and Marco Polo related of them, was long considered a groundless legend, and an oriental fiction. The narrations of the latter have not been less doubted and oppugned, than the traditions of Herodotus concerning the countries and nations of antiquity. The more, however, the east is opened by the study of languages and by travel, the greater confirmation do these venerable records of history and geography receive; and the veracity of the father of modern travel, like that of the father of ancient history, only shines with the greater lustre.