“Assassins (a word derived from Hashashin) is the name used to refer to the medieval Nizari Ismailis, an order led by a mysterious “Old Man of the Mountain.” They were an Islamic sect that formed in the late 11th century from a split within Ismailism, itself a branch of Shia Islam.
“The name Hashishin allegedly comes from the order’s penchant of indulging in hashish during ecstatic rituals.
“A Hashishin’s skill with a scimitar (a curved, single-edged sword which originated in the east) was, in legend at least, unmatched. The order was also skilled in the art of stealth and made a habit of murdering political opponents through the decades.
“While ‘Assassins’ typically refers to the entire medieval Nizari sect, in fact only a class of acolytes known as the fida’i (Fedayeen fida’iyin, “those who sacrifice themselves”) actually engaged in assassination work.
“Lacking their own army, the Nizari relied on these trained warriors to carry out espionage and assassination of key enemy figures, and over the course of 300 years successfully killed two caliphs, and many viziers, sultans and Crusader leaders.”
Credit to TIME Ishaan Tharoor, Friday, May 06, 2011