Most historians, if asked to choose the two outstanding popes during the centuries covered by this book, would point to Gregory VII and Innocent III. The two form a striking contrast both as personalities and as representatives of their times. Living in a society with undeveloped administrative structures, Gregory had pursued his aims by means of propaganda, exhortation, and symbol rather than by systems of control which would have been inconceivable to his contemporaries. Nor could the detailed regulation of the life of the faithful have any part in his aims. He desired that the church should be 'catholic, chaste and free', that is that the priesthood should be liberated from the ritual impurities of simony, concubinage, and lay control. His own positive achievement was very limited. His extreme policies had divided his supporters and forced him into exile from Rome, and the victory of his ideals, in so far as they were adopted, was the result of the skilful government of his successors.
Government by exhortation is a necessary part of the work of any pope and forms the ultimate basis of all papal authority. Nevertheless the development of society provided Innocent III with mechanisms for the consistent application of policy of which Gregory could not even have dreamed. A well-organized college of cardinals and central administration, a developing system of appeals to the curia and a canon law which looked to the Roman Church as the supreme arbiter were reinforced by other institutions which could be pressed into papal service: the international religious orders, the concept of the crusade, and the emergent universities were among them. By 1200 a major development anywhere within the western church was almost certain to require some reference to Rome. Innocent showed remarkable skill in the use of these resources and deployed them to meet the three external menaces to the Roman Church of which he was acutely aware: the loss of Jerusalem, heresy, and the Hohenstaufen dominance in central Italy. He was also convinced that the first two of these threats at least demanded as a response the