ONDŘEJ STOLIČKAIn the past, European historiography did not pay much attention to research on diplomatic relations between the Spanish monarchy and the northern parts of the Holy Roman Empire, especially during the reign of Charles II of Spain (1661-1700) In fact, there are no significant investigations of this period and this specific topic The situation looks a little bit better in the field of historical investigation, which has focused on the connec-tions between Spain and Central Europe However, this subject has never belonged to the main topics of Austrian, Czech, German, Hungarian, Polish or Spanish historiography The prime reason for this lack of attention may be the result of the language barrier on both sides of Europe, 1 and in patterns of historical development on this continent during the 20 th century 2 Despite these obstacles, a few historians were able to write on this topic during the 1 Czech historian Pavel Marek, in his article about the language barrier of Czech historians, mentioned this specifically, but is still necessary to mention that Spanish scholars also faced the same problem To date, only a small number of them are able to use German language-documents Pavel Marek,