Europe in the second half of the sixteenth century was a continent divided along confessional lines. Nowhere was this more apparent than in the Holy Roman Empire of the German Nation. While other countries, in particular France and the Netherlands, drifted toward religious war, the Empire seemed to have settled its religious problems with the Treaty of Augsburg in 1555. The treaty, which Emperor Ferdinand I had negotiated with the German princes, permitted Catholic rulers to impose Catholicism upon all their subjects and Lutheran princes to impose Lutheranism. This was a religiopolitical compromise that worked temporarily but became increasingly difficult to preserve as Germany's confessional picture continued to change in the late sixteenth and early seventeenth centuries.

A few months ago the musical world observed the centennial of the first complete performance of Richard Wagner's Der Ring des Nibelungen, which took place in the then barely completed Bayreuth Festspielhaus, August 13–17, 1876. Few works of art have had so long a gestation period; more than a quarter century separates Wagner's original sketches, which date from the fall of 1848, and the realization of the tetrology on the stage. The dramatic structure of the enormous music-drama became definitive by February 1853, when Wagner allowed to be printed privately the texts of the four operas. The music for Das Rheingold, Die Walküre, and the first two acts of Siegfried was complete by the end of July 1857. There followed, however, an interval of almost twelve years before Wagner again took up work on the Ring in March 1869. He composed the music for the final act of Siegfried and for all of Gütterdämmerung between then and November 1874.

Because of the politically sensitive and often quite unsavory aspects of their work, but also because they wish to protect their former agents, secret services usually do not like to say very much about their past activities and try to keep their records out of the hands of historians and other outsiders for as long as possible. The army intelligence service of Imperial Germany—officially known as the Geheime Nachrichtendienst des Heeres or, more simply, as the “N.D.”—was no exception to this rule. While the last chief of that organization, Walter Nicolai, and some of his former subordinates wrote a number of books and articles after 1918 in which they described the functions of the N.D. and some of its accomplishments, they remained studiously vague on many issues, particularly with regard to the espionage operations which had been conducted in the Entente countries in the years prior to the Great War. As might be expected, various other German publications on the background of the war which appeared in the 1920s and 1930s, including Die Grosse Politik der Europäischen Kabinette and other such editions of government documents, similarly maintained a discreet silence on this subject.