The director Max W. Kimmich was the brother-in-law of Joseph Goebbels as he was married to his younger sister Maria from 1938 until her death in 1949.
War prisoners from the french colonial troops of the Stalag III A in Luckenwalde, Brandenburg near Berlin and partly from Paris were used to portray the "black" characters.
Luis Trenker met the real Friedrich Karl Kleine and talked to him about the screenplay. According to Trenker's memories Kleine was angry about it and said "Herr Trenker, this is horrible what is written in the screenplay, it is all not true. The English helped us always and and everywhere and didn't block or fight our work".
While the real doctor Friedrich Karl Kleine was part of the production and was consulting the director during research he was not a part of the script development. he was worried about the own international name from the scientific point of view. Also he asked the UFA to ensure that his name will not be used for the promotion campaign.
King Wapunga is named after an African tribe "Wapunga" in Tansania, former colony "German East-Africa", which took part in the Maji-Maji-movement from 1905-1907.