As a young man, he was at loggerheads with his father, an Evangelical Lutheran pastor who admired Adolf Hitler and hoisted the swastika flag at his church well prior to the Nazi takeover in 1933.
[1] Cunz began his peripatetic university studies at Munich for one semester in 1929, before transferring to Leipzig, where he enrolled for three semesters and studied political and diplomatic history, the history of religion, and German literature, attending courses taught by Erich Brandenburg, Hans Driesch, Theodor Litt, H. A. Korff and Georg Witkowski.
Cunz chose to remain in Frankfurt to complete his Ph.D. dissertation on Johann Casimir of Simmern,[2] a staunch Calvinist who was a leader of mercenary troops in the religious wars of the sixteenth century, including the Dutch Revolt.
Hard pressed financially and unable to seek employment under the terms of their Swiss student visas, Koplowitz and Plaut relied on writing under pseudonyms as their primary source of income.
In addition, under the collective pen name Stefan Brockhoff, they coauthored with Cunz three detective novels that were published in Nazi Germany.
[3] Because he had enrolled in the Nazi Writers' Association (Reichsschrifttumskammer [de]) in 1934, Cunz was able to use his own name when he published in Germany a study of European constitutional history, Europäische Verfassungsgeschichte der Neuzeit (1936).
[6] Whereas Cunz was tolerated by the Swiss authorities and was entitled to work as a freelance journalist, Plaut and Koplowitz found it increasingly difficult to remain in Switzerland after their student visas expired with the completion of their doctorates.
Cunz was among the early specialists in German-American studies and authored numerous articles on German immigrants between the colonial period and the Civil War, such as the explorer Johann Lederer and the radical abolitionist Karl Follen.
[9] In 1939, Cunz was expelled from the Nazi Writers' Association and appointed to an instructorship at the University of Maryland, College Park, where he advanced to an assistant professorship in 1942.
He expected all departmental colleagues, including the literature specialists such as Seidlin, to shoulder their fair share of "service" courses, i.e., language instruction.
With Curtis C. D. Vail (1903–1957) of the University of Washington, Cunz coauthored German for Beginners (1958), a textbook that was widely adopted throughout the U.S.[11] It advanced beyond the traditional "grammar-translation" approach to the more communicative audio-lingual method and made use of language lab tapes.
Cunz edited an abridged version of Ricarda Huch's Der letzte Sommer, a "novel in letters set during the fight of the Russian anarchists against the Czarist regime", for use in German language instruction.