Nicknamed Abu al-Barakāt, Nethanel ben Mevorakh was the middle son of Mevorakh ben Saʿadya, who served as ra'īs (or colloquially rayyis) al-yahūd (Ar. head of the Jewish community, i.e. nagid) of Fustat from ca. 1078 to 1082 and from 1094 to 1111. Nethanel seems to have been born around 1095. Unlike his father and his brother Moses, Nethanel did not ascend to the headship. On the other hand, he was an active participant in the culture of the political and economic elite of his community, and may well have served the Fatimid court, as perhaps is indicated by allusions to him in Geniza documents t…