Innocent III: Leader of Europe, 1198-1216.

Innocent III (r.1198--1216) has been considered the greatest pope of the high Middle Ages: he launched the Fourth Crusade, sent an army against the Albigensians, convened the Fourth Lateran Council, and in his struggle for the supremacy of the spiritual over the temporal power, excommunicated both King John and the Emperor Otto IV. In him, many of the abiding concerns and contradictions of the medieval papacy are powerfully embodied. This study reassesses his life, achievements and impact, against their full European background.