This volume describes the life and work of Mainz’s archbishops between 1089 and 1200 – when the enforcement of the papal primacy articulated by Gregory VII and the development of territorial power in the archdiocese, stretching from the Rhein to the Saale, played a major role in archdiocesan politics. The archdiocese had an influence on imperial political decisions, as demonstrated by Adalbert’s I actions during the royal elections of 1125.