This Is the Forgotten Story of How Assassins Got Their Name
How the Nizari Ismailis came to be known as the Assassins is still the subject of much debate. Popular mythology maintains that their ominous name derived from their use of drugs such as opium and hashish to induce a fanatical frenzy in their killers. This myth was first carried back to Europe by the Crusaders, but did not become widely known in the West until it was published in the travelogues of Marco Polo. Polo discussed the workings of the Assassins in his book and even claimed to have visited Alamut. However, it should be remembered that he wrote his travelogues in the late 13th century, well after the Assassin period had come to an end.
Source URL (retrieved on April 8, 2018):
http://nationalinterest.org/blog/the-buzz/the-forgotten-story-how-assassins-got-their-name-25249
