Blessings to you, Garveys Africa. You inspired me to search Isaiah on Ethiopia. I did find a prophecy concerning babylon and slavery:
Thus saith the LORD, The labour of Egypt, and merchandise of Ethiopia and of the Sabeans, men of stature, shall come over unto thee, and they shall be thine: they shall come after thee; in chains they shall come over, and they shall fall down unto thee, they shall make supplication unto thee, saying, Surely God is in thee; and there is none else, there is no God.
It's followed with a happy ending, explaining the confusion of babylon and the victory of Jah's people in the end.
Verily thou art a God that hidest thyself, O God of Israel, the Saviour. They shall be ashamed, and also confounded, all of them: they shall go to confusion together that are makers of idols. But Israel shall be saved in the LORD with an everlasting salvation: ye shall not be ashamed nor confounded world without end. For thus saith the LORD that created the heavens; God himself that formed the earth and made it; he hath established it, he created it not in vain, he formed it to be inhabited: I am the LORD; and there is none else. I have not spoken in secret, in a dark place of the earth: I said not unto the seed of Jacob, Seek ye me in vain: I the LORD speak righteousness, I declare things that are right. Assemble yourselves and come; draw near together, ye that are escaped of the nations: they have no knowledge that set up the wood of their graven image, and pray unto a god that cannot save. Tell ye, and bring them near; yea, let them take counsel together: who hath declared this from ancient time? who hath told it from that time? have not I the LORD? and there is no God else beside me; a just God and a Saviour; there is none beside me. Look unto me, and be ye saved, all the ends of the earth: for I am God, and there is none else.