Policraticus

Policraticus is a work by John of Salisbury, written around 1159. Sometimes called the first complete medieval work of political theory, it belongs, at least in part, to the genre of advice literature addressed to rulers known as "mirrors for princes", but also breaks from that genre by offering advice to courtiers and bureaucrats. Though it takes up a wide variety of ethical questions, it is most famous for attempting to define the responsibilities of kings and their relationship to their subjects.