King David was described as a good looking red head (I Sam 17:42), and Moses was castigated by Miriam and Aaron for marrying a “Cushite” woman (Cush is the ancient Hebrew word for Ethiopia). So, the prototypical Israelite (David) was red head, and Cush seems to be thought of as ethnically “other” enough for it to warrant mention.
The mentioning of blacks Africans in rabbinic literature (Midrash, Mishnah, Talmud, etc.) shows pretty clearly that black people are considered ethnically other.
On the other hand, we know now that there has been a long existing black Jewish community in Ethiopa.
Ethiopian Jews say they are descended from King Solomon, through the queen of Shebe. In addition, it is quite likely that many Jews fled to Ethiopa during the Babylonian conquest.
It is important to know that “Semite” refers more to a language system than regular ethnic features. Any basic history of ancient middle east will show that there was always mass migrations up and down and across the region.
When I have traveled in Israel and Palestine, I never cease to wonder at the ethnic mix. I remember seeing a person with very pronounced Asian features, and I struck up a conversation with him. His Hebrew was fluent and accentless: his Jewish family had come from Tashkent – about 300 miles from China.
In Palestine, I met flaming red heads whom I thought were fellow Americans – nope – Arab Palestinians. Both were “Semites”, though.
In Israel, it can really be extreme: thousands of Russian immigrants, alongside of thousands of Ethiopian immigrants. Both would call themselves “Semites” . As far as we can tell, these kind of immigration patterns are not limited to modern world.