Fustat Egypt which sits on the River Nile - this is how the Jews called their city. Coalition and opposition, power struggles between leaders who were aided by local Jewish pressure groups and abetted by the Muslim authorities - these were a few of the characteristics of the leadership in the Jewish community of Fustat, the largest and liveliest of the Jewish communities in the eleventh century.The author follows the activities of these leaders and analyzes their motives in the light of the complex relationships developing in the community between the different ethnic groups, while in the background the traditional centers of Jewish authority in Palestine and Babylon battle each other for control of the Jewish people.The survey of the dramatic events was made by analysis of documents and letters from the Geniza in Cairo.