Eulenberg was the publisher of many books, for which he wrote the introductions. His speech on Schiller, which he wrote in 1909, generated heated debates. In 1911 he published Letter of a Father of our Times in the magazine PAN for which he was accused, tried and later acquitted of the charges of circulating obscene writing.
In the 1920s, he was one of the most performed playwrights on German stages. His essays on various subjects and topics on literature, theatre, music, and fine arts were published in numerous newspapers and magazines throughout Germany and Austria. He was awarded prizes and honours for his literary work such as “Der Preis des Frauenbundes zur Ehrung rheinischer Dichter”, the ”Volks-Schiller-Preis”, the “Preis of the Peter Wilhelm Müller Trust”, or the ”Wiener Volksschillerpreis”.
During Nazi Germany, Eulenberg's dramas were banned, his books were no longer printed or sold. Yet, he stood firm against the threats of party members, who continuously denounced the pacifist and humanist as a “red-haired Jew”. If it had not been for his great fame he would have ended up in a Nazi concentration camp.
During World War II, he published short articles under his pseudonyms “Siebenkäs”, “Lynkeus” or “Der lächelnde Zuschauer” in “Der Mittag”, a Düsseldorf daily newspaper. At the same time he wrote a multitude of dramas, in which he sharply attacked and disputed the current political situation.
After 1945 he was permanent contributor to the magazines “Aufbau” and “Die Weltbühne”. He received further prizes: 1948 the “Heinrich-Heine Prize” of the "Heinrich-Heine-Gesellschaft" at Hamburg for his biography of Heinrich Heine. In the cultural alliance for the democratic renewal of Germany he committed himself to the rebuilding of a cultural program for the bombed Düsseldorf. In 1948 he received an Honorary Doctorate from the University of Bonn. Eulenberg died in Düsseldorf-Kaiserswerth on September 4, 1949 of serious injuries after an accident. In 1949 he was posthumously awarded the Nationalpreis der DDR.
Johann Gottfried Hagens: Herbert Eulenberg. Berlin: Börngräber (1910). (= Der moderne Dichter; 4)
Peter Hamecher: Herbert Eulenberg. Ein Orientierungsversuch. Leipzig: Rowohlt (1911).
Oskar Maurus Fontana: Die Dramatiker des Rheinlandes. Herbert Eulenberg und Wilhelm Schmidtbonn. Augsburg: Filser (1921).
Rudi vom Endt: Der Dichter Eulenberg, ganz menschlich gesehen. Wuppertal-Elberfeld: Putty (1946).
Hedda Eulenberg: Im Doppelglück von Kunst und Leben. Düsseldorf: Die Faehre (1952).
Otto Brües: Herbert Eulenberg. Ansprache zu seinem Gedächtnis an seinem 80. Geburtstag am 25. January 1956 in der Staatlichen Kunstakademie. Düsseldorf: Gesellschaft von Freunden und Förderern der Staatl. Kunstakademie (1956).
Helgard Bruhns: Herbert Eulenberg. Drama, Dramatik, Wirkung. Frankfurt am Main: Akad. Verl.-Ges. (1974). ISBN3-7997-0239-3
Michael Matzigkeit: Herbert Eulenberg - "Siebenkäs", eine Opposition im Verborgenen. In: Musik, Theater, Literatur und Film zur Zeit des Dritten Reiches. Düsseldorf (1987), S. 89–95.
Michael Matzigkeit: Herbert Eulenberg - Der Prototyp des "rheinischen" Autors. In: Ders., Literatur im Aufbruch. Schriftsteller und Theater in Düsseldorf 1900 - 1933. Düsseldorf: Verl. d. Goethe-Buchh., (1990), S. 57 - 82; 214 - 221. ISBN3-924331-23-5
Frank Thissen: "Edle Arznei für den Alltag". Herbert Eulenbergs Düsseldorfer Morgenfeiern und die Romantikrezeption um 1990. Köln u.a.: Böhlau (1992). (= Böhlau forum litterarum; 16) ISBN3-412-06691-5 (can be demanded as PDF [1] by the author.)
Bernd Kortländer: Rheinischer Internationalismus am Beispiel Herbert Eulenbergs. In: Literarische Fundstücke, hrsg. v. Ariane Neuhaus-Koch u. Gertrude Cepl-Kaufmann. Heidelberg: Winter (2002). (= Beiträge zur neueren Literaturgeschichte; 188). S. 256–274. ISBN3-8253-1303-4
Joseph A. Kruse: Der Schriftsteller Herbert Eulenberg (1876–1949). Ein『Ehrenbürger der Welt』aus Kaiserswerth am Rhein. In: Geschichte im Westen. 18 (2003) S. 116–128.
Sabine Brenner: "Heinrich Heine hat mich gebeten, in seinem Namen folgendes zu erklären". Der ’rheinische’ Dichter Herbert Eulenberg und sein literarisches Vorbild Heinrich Heine. In: "... und die Welt ist so lieblich verworren", hrsg. v. Bernd Kortländer. Bielefeld: Aisthesis (2004). ISBN3-89528-465-3
