We cannot ascertain what position Nabonetus took up towards the growing power of Cyrus. According to the statement of Trogus Pompeius, Babylon was at war with Cyrus, when Croesus went to her aid. Cyrus repelled this attack, came to terms with Babylonia, and carried on war against Asia Minor. Xenophon represents Croesus as beginning the war against Cyrus at the request of the king of Babylon (p. 17). Herodotus, as has been mentioned above, repeatedly assures us that Croesus was in league with the king of Babylon, whom he calls Labynetus (p. 20). As we saw, Cyrus left Sardis and Asia Minor in the spring of 548 B.C., before the nations of the western coast, the Carians and Lycians, had been subjugated; and Herodotus remarks that he intended to march against Babylon. For Babylonia there could certainly be no more favourable moment for carrying on the war with the Persians than the time at which Cyrus lay opposite the army of Croesus at Pteria in Cappadocia, before he advanced upon Sardis. A march of the Babylonian army up the river Euphrates would have cut off the communications of the Persian army with their own home, and compelled Cyrus to abandon the Lydians and to turn upon Babylon. We do not know whether Nabonetus looked idly on at the fall of Croesus in spite of the league, or whether a second Persian army compelled him to leave events to take their course in Asia Minor, or whether Cyrus, on his return to Ecbatana, after the overthrow of Croesus, as Herodotus tells us, marched against Nabonetus. All that we know from Herodotus is that Harpagus subdued lower Asia, _i.e._ Asia Minor, and Cyrus himself upper Asia, passing from one nation to another without any exception.