Adam Clarke on Isaiah 14:25

I will break the Assyrian - upon my mountains "To crush the Assyrian - on my mountains" - The Assyrians and Babylonians are the same people, Herod. 1:199, 200. Babylon is reckoned the principal city in Assyria, ibid. 178. Strabo says the same thing, lib. 16 sub init. The circumstance of this judgment being to be executed on God's mountains is of importance; it may mean the destruction of Sennacherib's army near Jerusalem, and have a still farther view: compare Eze 39:4; and see Lowth on this place of Isaiah.