Not Caucasian, he's believed to be Ainu. There are 10-50,000 Ainu still alive on a northern island in Japan.
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THE SAMURAI AND THE AINU
Findings by American anthropologist C. Loring Brace, University of Michigan, will surely be controversial in race conscious Japan. The eye of the predicted storm will be the Ainu, a "racially different" group of some 18,000 people now living on the northern island of Hokkaido. Pure-blooded Ainu are easy to spot: they have lighter skin, more body hair, and higher-bridged noses than most Japanese. Most Japanese tend to look down on the Ainu.
Brace has studied the skeletons of about 1,100 Japanese, Ainu, and other Asian ethnic groups and has concluded that the revered samurai of Japan are actually descendants of the Ainu, not of the Yayoi from whom most modern Japanese are descended. In fact, Brace threw more fuel on the fire with:
"Dr. Brace said this interpretation also explains why the facial features of the Japanese ruling class are so often unlike those of typical modern Japanese. The Ainu-related samurai achieved such power and prestige in medieval Japan that they intermarried with royality and nobility, passing on Jomon-Ainu blood in the upper classes, while other Japanese were primarily descended from the Yoyoi." The reactions of Japanese scientists have been muted so. One Japanese anthropologist did say to Brace," I hope you are wrong."
The Ainu and their origin have always been rather mysterious, with some people claiming that the Ainu are really Caucasian or proto-Caucasian - in other words, "white." At present, Brace's study denies this interpretation.
There are other traits shared in roughly those proportions throughout the Japanese population.
It is wrong to give a number on the surviving Ainu ~ just about everyone in Japan has Ainu ancestry.
The Ainu might have been a European people. The oldest pictures of them show red hair and beards, as well as taller stature than modern day Japanese. Why else would they be discriminated against?