Unnatural hair colours did exist in the past!
Yes they did, Older women where often seen with a blue or lavender rinse on their white/gray hair.
My grandmother told me that when she was a young woman in the 30s and early 40s that it was quite popular for a time for 20s and 30s aged women to go with an extreme platinum look like Jean Harlow and wear a bright colored rinse over the top (just like the ones above) for a fashionable change.
Barbie fashion illustration 1960s
The ‘bubble flip’.
Models in wigs wearing sheath dresses for the Sears catalogue, 1963.
International Nurse Uniform Photograph Collection (ca.1950)
Lambretta Scooter, 1950s