Jamieson, Fausset and Brown on Isaiah 24:21

21. host of ... high ones--the heavenly host, that is, either the visible host of heaven (the present economy of nature, affected by the sun, moon, and stars, the objects of idolatry, being abolished, Is 65:17; 60:19, simultaneously with the corrupt polity of men); or rather, "the invisible rulers of the darkness of this world," as the antithesis to "kings of the earth" shows. Angels, moreover, preside, as it were, over kingdoms of the world (Da 10:13, 20, 21).