In 1979, Japan was in the Dark Ages. Dark that is, in terms of hair. No one dyed their hair any other color but black and when they reached for lighter tints, were considered a bit on the bizarre side.
There was one woman singer called Mina Aoe, who built her career on an auburn hair-do but she was a lone pioneer, a single spot of color in an ocean of black. Schoolgirls especially, were banned from hair activities like dying, curling and setting -- all grooming prerequisites for today's 7th graders.
On my first day in junior high school, we were told that a student adding any sort of "artifice" to her hair, including the use of colorful barrettes or other accessories during school hours, would be tried and punished.