*sub Saharan not south
I'm not entirely sure what you mean by this question. Egypt was a rather xenophobic society, and they did revs to exclude outsiders. However, most of the groups you mentioned were, at one point or another, conquers and t rulers of Egypt (ie, hyksos, ptolemaic, persians). What tends to happen is that the group takes over and is either gradually assimilated, or quickly kicked out.