When being in the UFA-Studios Fallada said that he has never written a screenplay before. This is not entirely true as he had various requests from UFA to write dialogues for movies, e.g. in 1935 or for an planned adaptation of "Wer einmal aus dem Blechnapf frißt".
Walter Hasenclever killed himself in 1940, not in 1943, as suggested by Else-Marie Bukonje.
Hans Fallada said that Joachim Ringelnatz killed himself. IN real life he died of tuberculosis.
It is not 100% clear if Rudolf Ditzen aka Hans Fallada got his pseudonym from Grimm's fairy-tales "Hans in luck" and "The Goose Girl". It is considered only a Theory. In the movie it is stated as a fact.