In line with the new approaches that arose during the second half of the twentieth century in the history of medicine and the history of diplomacy, fields which today are known to be highly interrelated, the article aims to undertake a historiographical assessment of the court physician as political “mediator”. There are a variety reasons for this overlapping of roles and functions: not only the physician’s access to the inner entourage of the prince and his proximity to the sovereign’s body, but also the many different aspects of medical knowledge that appeared to be vitally important for the exercise of diplomacy: the ability to interpret moods and signs in a face-to-face encounter, to evaluate them in the light of experience and classify them into concepts that can be interpreted historically. Moreover, while the existing literature is not vast, it does document numerous case-studies of physicians who were also political informers, diplomats and historians and who acted as go-betweens among courts, countries and even religious confessions. The authors hope that systematic research will continue to be done in this direction.