What was the nationality of the author of the outline that Die Liebe der Danae is based on?
Die Liebe der Danae Die Liebe der Danae ("The Love of Danae") is an opera in three acts by Richard Strauss to a February 1937 German libretto by Joseph Gregor, based on an outline written in 1920, "Danae, or The Marriage of Convenience", by Hugo von Hofmannsthal. Strauss worked on the score in 1937, 1938 and into 1939, although he was pre-occupied with completing "Daphne", developing ideas with Gregor and finally replacing him as librettist for "Capriccio", and then succumbed to illness, which caused postponement for several months into 1940. The opera was finally finished on 28 June 1940.
Joseph Kastein Josef (later Joseph) Kastein, really Julius Katzenstein (6 October 1890 – 13 June 1946), was a German-born writer and jurist. He wrote "Eine Geschichte der Juden" published by Rowohlt in Berlin in 1931 (translated into English, Hebrew and Dutch).