PC and History

Why is it that Film Producers try and change History? It seems that Jamie Fox a Black actor is to play Little John in a new version of Robin Hood. If any of you will have read books on Robin Hood you will note that Little John was an Anglo Saxon which was a white person. The TV programme MERLIN featured many of the Knights as Black and many of the peasants as Black what in 5th Century England? Some historians claim there was one Black Knight a Sir Morien but you have to look at who has suggested this and their PC background. I enjoy Murdoch Mysteries but found it strange that in 1900 Toronto there was a Black Doctor and many Black Middle class people plus Black and White couples this is not factual and is insulting to Black People who fought hard to get equality.
Would a White Actor playing Nelson Mandela or in a remake of Zulu have the Zulu Chief portrayed by a White Actor? No it would be ridiculed and be called racist. The idea of a white actor Blacking up has gone so we are now seeing the opposite which just as wrong
The Left-wing Luvvies think they have the right to change History by trying to apply modern day sensitivities to the past. Some parts of History never pleasant but they are facts and can not be white washed no matter what the Luvvies think