In the Middle Ages, representation was important as a legitimizing principle of sacralized rule (representation of God/Christ on earth); but it was also omnipresent as a necessary instrument of lordship in political and ecclesiastical, but also economic, legal, and social life. Nevertheless, in historical research - in contrast to theology and legal history - this phenomenon is examined rarely. Above all, there is little in-depth research on the concepts as well as on the forms of representation, including their differences in terminology and contents. The aim of this volume is to examine and compare concepts, agents and signs of primarily religiously connotated or clerically based representation in the Christian Western and Eastern Churches, Islam, the Mongol Empire and Japan.