1013 (10 Iyar 4863) - 1103 ISAAC ALFASI (Fez, Morocco)
Also known as the "RIF", compiled the first codification of Jewish law, entitled Sefer Halachot. It still appears today in every volume of the Talmud. Joseph Caro later used it as a basis for his work. Sefer Halachot was the most important codex until Maimonides' Mishna Torah. Alfasi was 25 years old when Hai Gaon died. He was called Gaon by many authorities and his death marked the very end of the Geonic Period (since 589), although there are others who say that the Geonic Period ended with the death of Hai Gaon (1038). His students included Judah Halevi and Josef ibn Migash.