Natronai ben Hilai was Gaon

Gaon (Hebrew)

Gaon originally referred in Ancient Hebrew to arrogance and haughty pride . Later became known as pride in general: whether good or bad . Today it may refer to:...

 of the academy at Sura

Sura

A sura is a division of the Qur'an, often referred to as a chapter. The term chapter is sometimes avoided, as the suras are of unequal length; the shortest sura has only three ayat while the longest contains 286 ayat...

 early in the second half of the 9th century; he succeeded Sar Shalom. His father had occupied the position about thirty years before. Although Naṭronai was of advanced age when he entered on the office, and although his official term embraced less than a decade, an unusually large number of responsa

Responsa

Responsa comprise a body of written decisions and rulings given by legal scholars in response to questions addressed to them.-In the Roman Empire:Roman law recognised responsa prudentium, i.e...

 were issued by him. Questions were addressed to him from all parts of the Jewish Diaspora

Jewish diaspora

The Jewish diaspora is the English term used to describe the Galut גלות , or 'exile', of the Jews from the region of the Kingdom of Judah and Roman Iudaea and later emigration from wider Eretz Israel....

; and his answers, about 300 of which have been preserved in various compilations (e.g., in Sha'are Ẓedeḳ, Teshubot ha-Ge'onim, and Ḳebuẓat ha-Ḥakamim), show his thorough mastery of the subjects treated as well as his ability to impart knowledge.