Isaiah ch.14 - Fallen From Heaven

Chapter 13 and 14 - the Pronouncement against Babylon - depicts the fall of a superpower and its leader who has "fallen from the heavens" to Sheol, whose body has been strewn like the war-dead, and not brought to royal burial. These events correspond to a very real event in history. The death in war of Sargon, the Assyrian king, in 705 BCE. So is this the "Pronouncement against Babylon" or is actually The Pronouncement about Assyria?