Hezekiah Gaon was gaon of the Talmudic academy at Pumbedita from 1038-40. Hezekiah was a member of the exilarchal family. He was elected to the office of principal after the murder of Hai Gaon, but was denounced to the fanatical government of the Buyyids, imprisoned, and tortured to death. With him ended his family, with the exception of two sons who escaped to Spain, where they found a home with Joseph ben Samuel, the son of Samuel ha-Nagid. Wikipedia
The definitive Wikipedia entry for Hezekiah Gaon. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Hezekiah_Gaon