>>280932778It goes back to China (as most things do with older Japanese culture) and the fact that the culture that became Japan was founded by an ethnic stock that doesn't take to growing facial hair very well (see:
>>280932845 ). The original imperial courts of Japan were essentially all Yayoi stock, and once Japan started imitating Chinese imperial culture they also brought over Chinese fashions, which included the fetishization of pale, smooth skin. Not just for women, but men too.
The time period I'm talking about here is like 700 AD. At this time "Japan" did not encompass all of modern day Japan, it occupied maybe half of Honshu (the southern part) and most of Shikoku and Kyushu. Northern Honshu was inhabited by a people the contemporary Japanese sources called the Emishi, who we can now identify with modern DNA evidence as descendants of both the Ainu and Jomon peoples, with a little bit of Yayoi admixture. I won't get into details but originally Japan was dozens of different petty kingdoms made up of Yayoi and Jomon populations intermixing, and eventually one of those petty kingdoms (Yamato) got the others to submit, founding the "Empire" of Yamato, which then later styled itself as Nihon (Japan). So basically not all of the population that lived on the islands had been subjugated by Yamato, some people were still independent and living in their own petty kingdoms and communities, and that included the Emishi. We don't know a whole lot about these people because the Japanese dismissively only referred to them as "Northern Barbarians" and only really mentioned them if some warrior fought a notable battle against them. Eventually though they were conquered and folded into the empire, though some small pockets remain of older Emishi DNA and culture, like the Matagi mountain men who live in Tohoku.
Ainu people don't have much genetic impact on modern Japan, but had a strong cultural impact on the Emishi of northern Honshu.