Archdeacon Hildebrand, who became Pope Gregory VII (r. 1073–85), is associated with a radical and swift change in the Roman Church. The vision of a Christendom jointly administered by emperor and clergy, the famous model advanced by Pope Gelasius II (r. 492–96), was transformed into a new order where regnum and sacerdotium occupied separate stacked spheres, with the spiritual claiming superiority. Unlike tenth-century reform movements, the later eleventh-century Roman reforms centered on the papacy. Popes assembled a curia featuring more professional officials, legates, councils, and other technologies of power. The reformed Church cultivated trained lawyers and sympathetic lay leaders. It has been credited with launching a legal “big bang,” the invention of propaganda, the creation of a semi-institutionalized public sphere, and the formation of a persecuting society. Closer examination of institutional changes helps reveal the achievements and limits of this “new world order.”