Castle of the Assassins
“The Assassin Cult, a name that may be derived from the Arabic “hashashin,†meaning hashish user, is surrounded in mystery and legend. This is in part because they were secretive, but also because the historical record we have of their activities is written from many different and conflicting perspectives. One of the best known of these, and probably least accurate, is that of Marco Polo. He is supposed to have visited Alamut in 1273, seventeen years after it was destroyed by the Mongols. The Mongols, under Hulagu Khan, grandson of Genghis, had proceeded from Alamut to sack Baghdad in 1258 and Damascus in 1260.”
Iran’s Castle of the Assassins in the National Geographic. I first heard of the hashashin in Terry Jones’ series The Crusades.