GAON (Heb. for "Excellency," plural Geonim), the title given to the heads of the two Jewish academies in Babylonia, Sura and Pumbeditha. Though the name is far older, it is chiefly applied to Rabbis who lived between the close of the Talmud and the transference of the centre of Judaism from Asia to Europe - i.e. from the end of the 6th to the middle of the 11th century A.D. The Geonim were required to do homage to the Exilarchs (see Exilarch) but were otherwise independent. They exercised wide authority and were appealed to in settlement of the social and religious affairs of the diaspora. To them must be assigned the arrangement of the main lines of the present Synagogue liturgy. Their chief literary activity took the form of Answers to Questions - a form which was extensively used in later centuries. The most noted of the Geonim, who will be found treated under their respective names, were Ahai, Amram, Ṣemach, Saadiah, Sherira and Hai. Hai Gaon died in 1038, closing the period of the Geonim after an activity of four and a half centuries.
A full list of the Geonim is given in tabular form in the Jewish Encyclopaedia, vol. v. p. 571.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)