CRM grew from Human Factors (try googling that).
I did a Human Factors course with my degree in the mid-sixties, when it was already a well-established but not a particularly well-known discipline. I think there is a professional body dating from the mid-fifties. Certainly by the early sixties there were academics trying to relate human factors to aviation. The term CRM didn't appear until much later, but the basic ideas were around then, although not yet widely accepted in the industry.
Let us know what you find out.