Hasdai Ibn Saprut - Physician to Abd Ur Rahman and Hakam II, Umayyad rulers in Cordova. Together with Moses ben Chanoch, he founded the Talmudic school in Cordova. For the next 350 years this school's influence was felt in Spain. He made contact with Joseph, King of Khazars, and served him as diplomat and interpreter, always using his position to help and protect his fellow Jews, including those in Byzantium.