Ernst Kantorowicz Ernst Hartwig Kantorowicz ( May 3 , 1895 – September 9 , 1963 ) was a German historian of medieval political and intellectual history and art , known for his 1927 book " Kaiser Friedrich der Zweite " on Holy Roman Emperor Frederick II , and " The King ' s Two Bodies " ( 1957 ) . Biography . Kantorowicz was born in Posen ( Polish : Poznań , then in Prussia ) to a wealthy , assimilated German - Jewish family and as a young man was groomed to take over the family business ( primarily liquor distilleries ) . He served as an Officer in the German Army for four years in World War I , he decided not to return to the business world , but went instead to study philosophy at the University of Berlin , at one point also joining a right - wing militia that fought against Polish forces in the Greater Poland Uprising ( 1918 - 1919 ) and helped put down the Spartacist uprising in Berlin . The following year , he moved to the prestigious University of Heidelberg to study history with Karl Hampe and Friedrich Baethgen , two noted medievalists . While in Heidelberg , Kantorowicz became involved with the so - called Georgekreis , a group of artists and intellectuals devoted to the German poet and aesthete Stefan George and who shared an interest in art , literature and Romantic mysticism . His association with the elitist and culturally conservative Georgekreis inspired Kantorowicz ' s unorthodox , aesthetic - cultural biography of the great Holy Roman emperor Frederick II published in German in 1927 and English in 1931 . Instead of offering a more typical treatment of laws , institutions and important political achievements , the book took a decidedly poetic turn , portraying Frederick as an idealized spiritual , as much as political , leader of the German nation . The work elicited a combination of bewilderment and criticism from the mainstream historical academy . Reviewers complained that it was literary mythmaking and not a work of serious historical scholarship . As a result , Kantorowicz published a hefty companion volume ( " Ergänzungsband " ) in 1931 which contained detailed historical documentation for the biography . Despite the furor over the Frederick book , Kantorowicz received an appointment to an academic chair at the University of Frankfurt . In 1933 , Kantorowicz had to resign his university position due to Nazi racial policies . Upon leaving , he took up a teaching position for a short time at Oxford before moving to the University of California , Berkeley in 1939 . After a controversy prompted by his reaction to McCarthyism ( he refused to take a loyalty oath required of all UC employees ) , he moved to the Institute for Advanced Study in Princeton . Not long after arriving in Princeton , he published his masterpiece , " The King ' s Two Bodies " ( 1957 ) , which explored , in the words of the volume ' s subtitle , " medieval political theology . " In particular , the book traced the ways theologians , historians and canonists in the Middle Ages and early modern period understood the office and person of the king , as well as the idea of the kingdom , in corporeal and organological terms . The figure of the European monarch was a unique product of religious and legal traditions that eventually produced the notion of a " king " as simultaneously a person and an embodiment of the community of the realm . The book remains a classic in the field . Kantorowicz was the subject of a controversial biographical sketch in the book " Inventing the Middle Ages " ( 1991 ) by the late Canadian medievalist , Norman F . Cantor . Cantor , who knew Kantorowicz at Princeton , suggested that , but for his Jewish heritage , Kantorowicz ( at least as a young scholar in the 1920s and 1930s ) could be considered a Nazi in terms of his intellectual temperament and cultural values . Cantor compared Kantorowicz with another contemporary German medievalist , Percy Ernst Schramm , who worked on similar topics and was a member of the Nazi Party . Kantorowicz ' s defenders ( particularly his student Robert L . Benson ) responded that although as a younger man Kantorowicz embraced the Romantic ultranationalism of the George - Kreis , he had only disdain for Nazism and was a vocal critic of Hitler ' s regime .