The English translation of Slovenian writer Vladimir Bartol (1903-1967), who originally finished his most prominent novel in 1937, came out some 3 years ago. Though based on real historical figure, the life and legend of the original "assassin", the old man on the mountain, 11th century Ismaili leader Hasan ibn Sabbah, it is by no means a factual account of history. Nevertheless, the book gained new popularity after the events of 9/11. The story of Alamut is set in northern Persia in 1092, but read through today's perspective, some might argue that it "transforms itself into a nightmare novel of the new century." (Olivier Maison, Journal de la Culture) Some even go so far as to equate ibn Sabbah, a man revered by millions for his brilliance and disdained by countless others for the reign of terror he spawned with his suicide missions, to Osama bin Laden. ibn Sabbah has inspired scores of other writers throughout the centuries, including Rimbaud, Nerval, Borges and William Burroughs.
Here's some more info on the book