Nasir Khusraw was an Iranian Isma'ili poet, philosopher, traveler, and missionary for the Isma'ili Fatimid Caliphate. September 9, 1004 – 1088; died at about 83. Alive at the same time as Avicenna, William the Conqueror, Leif Erikson, Anselm of Canterbury, and Judah Halevi. Wiki link