I'm not very knowledgeable on this subject. I've read along the way that the real Ark of the Covenant was supposed to be in Ethiopia hidden somewhere. I don't know how true that is, but it is a possible connection that the Ethiopians claim gives them legitimacy as one of the lost tribes of ancient Israel. I do know that Israel takes in many black Jews as part of the Aliyah or the return from the Diaspora. So there is that.