The terms « dynatoi» (the potents) and «epiphaneis» (the prominents) emerge in Byzantine narrative and juridic texts during the Middle Byzantine period. They designate dignitaries of the administration and the Church, great landowners and generally members of the ruling class, who oftenly abused their power or their influence on the expence of their neighboring and other landowners. From the 10th C. onwards, and from the reign of Romanos I until that of Basil II, the imperial administration is trying to put a limit to their power, my means of fiscal measures and reforms, such as the tax «allelegyon». We don't find any references to the dynatoi after 1037.