One of this movie's technical advisors was a Zulu Princess, and the tribe's historian. She knew the battle strategy perfectly, and drew it on the sand. Director Cy Endfield shot it exactly as she drew it.
Michael Caine earned £4,000 for his role, by far the most he had ever earned for a film part to that time. Within five years, he had become not only a big star, but a millionaire. Curiously, the film gives him an "introducing" credit, although he had been a frequent film actor (in mostly very small, but often credited, roles) for nearly eight years, and had lately had prominent TV and stage parts. Stanley Baker and Jack Hawkins were the highest paid actors in the film, with £30,000 each.
Chief Mangosuthu Buthelezi, who comes from a long line of Zulu warriors and royalty, played his great-grandfather, King Cetewayo. In an interview, he said the director had identified a radio announcer to play the part, "but when he saw me he said that he saw a family resemblance and persuaded me to take part as an extra."
Director Cy Endfield wanted a camera crane that was lightweight when disassembled, so it could be packed and transported through the African bush. Ken Eddy designed the first Filmair Giraffe camera crane for the job, starting the world's best-known camera crane company. This key piece of gear is still used in the film industry.
The Zulu extras, who had never seen a movie, had trouble understanding what they were doing playing to a camera. Stanley Baker sent to Johannesburg for silent movies, and showed Harold Lloyd, Stan Laurel, Oliver Hardy, and Buster Keaton, which the Zulus loved.