Watched one of the BBC moon landing programs on yesterday which touched on the story of Ed Dwight (first black astronaut). Apparently someone thought the program needed a black guy, but then this was the 60's, and black guys didn't get selected on merit in those days.
An able aviator, Dwight was selected, and sent to Test Pilot school at Edwards AFB. Apparently, during his time there, director of training, Chuck Yeager (yes, that Chuck Yeager) told all the white guys on the course not to talk to him, or otherwise fraternise with him.
I never had Chuck down as a massive racist, but then I suppose this was the norm.
Needles to say, Ed didn't make it through the later stages of astronaut training and was chopped from the program as a result of 'racial politics' to use his own words.
https://en.wikipedia.org/wiki/Ed_Dwight