Hirschfeld, communist jew that besides that book was also doing sexual experiments which even today would land him in jail: https://www.amerika.org/texts/the-origins-of-%E2%80%98racism%E2%80%99-the-curious-beginnings-of-a-useless-word-samuel-francis/

That word was exclusively created as attack word against native europeans, still used that way today by the same religious and political groups.