In the literal sense an assassin was a person who used cannabis. The root of the word, which entered English in the 16th century from either French or medieval Latin, is the Arabic ḥašīšī ‘hashish eater’, and it was first used in reference to the Nizari branch of Ismaili Muslims who ruled part of northern Persia in the 12th and 13th centuries, during the time of the Crusades. Renowned as militant fanatics, they were reputed to use hashish before being sent to murder the Christian leaders.