The reign of Pope Gregory VII (1073-85), who gave his name to an era of Church reform, is critically important in the history of the medieval church and papacy. Thus it is surprising that this is the first comprehensive biography to appear in any language for over fifty years. H. E. J. Cowdrey presents Gregory’s life and work in their entirety, tracing his career from early days as a clerk of the Roman Church, through his political negotiations, ecclesiastical governance, and final exile at Salerno. Full account is taken of his turbulent relations with King Henry IV of Germany, from his first deposition and excommunication in 1076, to the absolution at Canossa and the imposition of a second sentence in 1080. Pope Gregory was also a contemporary of William the Conqueror, and, as the author shows, fully supported his conquest of England. Gregory VII is presented as an individual whose deep inner belief in iustitia (righteousness) did not waver in the face of new circumstances, although his broad outlook underwent changes. Deeply committed to the traditions of the past and especially to those of Pope Gregory the Great, his reign prepared the way for an age of strong papal monarchy in the western Church.