Nehemiah bar Kohen Ṣedeq Gaon served as gaon of the academy of Pumbedita from 960 to 968. He was apparently of priestly descent. Nehemiah led an emerging faction against Aaron Sarjado after the latter, a member of the merchant class rather than the scion of a gaonic family, was appointed gaon of the academy of Pumbedita in 943. The immediate cause of Nehemiah’s secession was Aaron’s decision to appoint Sherira ben Hananiah and not Nehemiah to the post of av bet din ("president of the court" -- the second-highest rank in the yeshiva hierarchy) following the death of the incumbent av bet din, Amra…