The Mongols--Hoolagoo sent against the Ismaïlites--Rukn-ed-deen submits--Capture of Alamoot--Destruction of the Library--Fate of Rukn-ed-deen--Massacre of the Ismaïlites--St. Louis and the Assassins--Mission for the Conversion of the People of Kuhistan--Conclusion. Half a century had now elapsed since the voice of the Mongol seer on the banks of the Sélinga had announced to the tribes of that race that he had seen in a vision the Great God sitting on his throne and giving sentence that Temujeen, one of their chiefs, should be Chingis Khan (_Great Khan_), and the obedient tribes had, under the leading of Temujeen, commenced that career of conquest which extended from the eastern extremity of Asia to the confines of Egypt and of Germany. At this time the chief power over the Mongols was in the hands of Mangoo, the grandson of Chingis, a prince advantageously made known to Europe by the long abode of the celebrated Venetian Marco Polo at his court. The Mongols had not yet invaded Persia, though they had, under Chingis himself, overthrown and stripped of his dominions the powerful sultan of Khaurism. It was however evident that that country could not long escape the fate of so many extensive and powerful states, and that a pretext would soon be found for pouring over it the hordes of the Mongols. We are told, though it seems scarcely credible, that ambassadors came from the Khalif of Bagdad to Nevian, the Mongol general who commanded on the northern frontier of Persia, requiring safe conduct to the court of Mangoo. The object of their mission was to implore the great khan to send his invincible troops to destroy those pests of society the bands of the Ismaïlites. The prayer of the envoys of the successor of the Prophet was supported by the Judge of Casveen, who happened to be at that time at the court of Mangoo, where he appeared in a coat of mail, to secure himself, as he professed, from the daggers of the Assassins. The khan gave orders to assemble an army; his brother Hoolagoo was appointed to command it, and, as he was setting forth, Mangoo thus addressed him:-- "With heavy cavalry and a mighty host I send thee from Tooran to Iran, the land of mighty princes. It behoves thee now strictly to observe, both in great and in small things, the laws and regulations of Chinghis Khan, and to take possession of the countries from the Oxus to the Nile. Draw closer unto thee by favour and rewards the obedient and the submissive; tread the refractory and the rebellious, with their wives and children, into the dust of contempt and misery. When thou hast done with the Assassins begin the conquest of Irak. If the Khalif of Bagdad comes forward ready to serve thee, thou shalt do him no injury; if he refuses, let him share the fate of the rest."