anime history - When & where did the unnatural hair color aka You gotta have blue hair trope originate? - Anime & Manga Stack Exchange

I specifically want to know which manga or anime started the trend, so I can reason from there to the how question, in order to not make general assumptions. There was a time in manga/anime where

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anime history - When & where did the unnatural hair color aka You gotta have blue hair trope originate? - Anime & Manga Stack Exchange

Did the trope of 'You Gotta Have Blue Hair' originate in anime and manga, or can it be seen in enough older works to determine a different origin? Is there any official

Why is it that anime characters are often drawn with unnatural hair colors? (pink, red, blue, and similar bright colors)? - Quora

anime history - When & where did the unnatural hair color aka You gotta have blue hair trope originate? - Anime & Manga Stack Exchange

Did the trope of 'You Gotta Have Blue Hair' originate in anime and manga, or can it be seen in enough older works to determine a different origin? Is there any official

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Why can anime characters be born with any hair color? - Quora

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anime history - When & where did the unnatural hair color aka You gotta have blue hair trope originate? - Anime & Manga Stack Exchange