The introduction explains the state of the scholarship regarding the sanctity of the state, starting with what is commonly believed. Sulovsky then traces the argument back to its intellectual roots, in the process showing that it is based on false premises that had more to do with the clash of Catholic and Protestant worldviews than with any medieval reality per se. The introduction of the phrase sacrum imperium, the translation of the Three Kings and the canonisation of Saint Charlemagne constituting a triad of sacralising acts is traced to Heinrich Appelt, the senior diplomatist who edited Frederick I’s diplomata. However, as Sulovsky shows, Appelt drew heavily upon Friedrich Heer, whose magnum opus Die Tragödie des Heiligen Reiches deeply influenced many scholars, though he is only reluctantly cited by them. Heer’s work is then shown to be a Catholic response to the Kulturkampf-dominated Prussian school, which formulated the original idea of the sacralisation of the state in 1910, but based on eighteenth-century German Protestant interpretations of imperial history. Thus, the introduction demonstrates that much of our knowledge rests on the presuppositions and axioms of a bygone ideological struggle.