By coincidence I was reading an old copy of Militaria this week which had an article by Ian Knight on Zulus and film. There were several before Zulu none really notable. In 3 parts - The Movie History of the Zulu Wars.
It seemed that Michael Caine was earmarked for the part of Hook - typecasting. They've gone an' bloody well blown the doors off the 'ospital. OK Italian Job was later.
Michael Caine did appear with Stanley Baker in the earlier film A Hill in Korea and there is a feel of the Imjin river rearguard about this film and in Zulu itself. Caine actually fought in the Korean War. Caine relating to a flashback to Korea, as to how he could smell his fear in the form of the stench of the Chinese hordes of infantry they could smell coming during an attack . . .
So how much of Zulu was a reliving of those Korean war experiences? I feel the film Zulu and the intepretation of the events was shaped by the Korean War ( or the British involvement in) and the liberties taken with the film's characters was part and parcel of that.

David