In the 1960s, Riefenstahl became interested in Africa from Ernest Hemingway's "Green Hills of Africa" and from the photographs of George Rodger. She visited Kenya for the first time in 1956 and later Sudan, where she photographed Nuba tribes with whom she sporadically lived, learning about their culture so she could photograph them more easily. Even though her film project about modern slavery entitled "Die Schwarze Fracht" ("The Black Cargo") was never completed, Riefenstahl was able to sell the stills from the expedition to magazines in various parts of the world. While scouting shooting locations, she almost died from injuries received in a truck accident. After waking up from a coma in a Nairobi hospital, she finished writing the script, but was soon thoroughly thwarted by uncooperative locals, the Suez Canal crisis and bad weather. In the end, the film project was called off. Even so, Riefenstahl was granted Sudanese citizenship for her services to the country, becoming the first foreigner to receive a Sudanese passport.