of the Tigris River ran through the middle of Assyria, while mountains hemmed it in on the north and east. Assyrian armies often operated in those mountains and extended Assyrian authority into present-day eastern Turkey to the north and western Iran to the east. For our study of the book of Nahum, however, we are more interested in the expansion of the empire to the southeast into Babylon and west to the Euphrates River and beyond. At the time Nahum wrote, the Assyrian Empire was at the height of