Although the book “Persia or Iran? The Germans discovering the land of Zarathustra” is not directly engaged with answering this question, the reader can acquire here the necessary background knowledge regarding the discovering of Ancient Iran by Germans, which enables him to make an informed opinion. “Persia or Iran” deals with the reception of the Iranian culture within the German-speaking world from its beginning in the 15th century to the present. In various chapters, it is presented, how the Germans came into contact with the Iranian culture and how they grappled with this culture. This book is both a reference work in which, both the German (forgotten) historical figures and their works are re-discovered and completely described. Thus, this volume aimes to address the interests of not only the general readership, but also the historians, Germanists, religious scholars, Orientalists and Iranists.