The aims of Cyrus were different from those of ordinary rebel satraps; and we must go back to the times of Darius Hystaspis in order to find a parallel to them. Instead of seeking to free a province from the Persian yoke, or to carve out for himself an independent sovereignty in some remote corner of the Empire, his intention was to dethrone his brother, and place on his own brows the diadem of his great namesake. It was necessary for him therefore to assume the offensive. Only by a bold advance, and by taking his enemy to some extent unprepared, and so at a disadvantage, could he hope to succeed in his audacious project. It is not easy to see that he could have had any considerable party among the Persians, or any ground for expecting to be supported by any of the subject nations. His following must have been purely personal; and though it may be true that he was of a character to win more admiration and affection than his brother, yet Artaxerxes himself was far from being unpopular with his subjects, whom he pleased by a familiarity and a good-nature to which they were little accustomed. Cyrus knew that his principal dependence must be on himself, on his Greeks, and on the carelessness and dilatoriness of his adversary, who was destitute of military talent and was even thought to be devoid of personal bravery.
Thus it was important to advance as soon as possible. Cyrus therefore quitted Sardis before all his troops were collected (B.C. 401), and marched through Lydia and Phrygia, by the route formally followed in the reverse direction by the army of Xerxes, as far as Celsense, where the remainder of his mercenaries joined him. With his Greek force thus raised to 13,000 men, and with a native army not much short of 100,000, he proceeded on through Phrygia and Lycaonia to the borders of Cilicia, having determined on taking the shortest route to Babylon, through the Cilician and Syrian passes, and then along the course of the Euphrates. At Caystrupedion he was met by Epyaxa, consort of Syennesis, the tributary king of Cilicia, who brought him a welcome supply of money, and probably assured him of the friendly disposition of her husband, who was anxious to stand well with both sides. In Lycaonia, Cyrus divided his forces, and sending a small body of troops under Menon to escort Epyaxa across the mountains and enter Cilicia by the more western of the two practicable passes he proceeded himself with the bulk of his troops to the famous Pylae Cilicias, where he probably knew that Syennesis would only make a feint of resistance. He found the pass occupied; but it was evacuated the next day, on the receipt of intelligence that Menon had already entered the country and that the fleet of Cyrus--composed partly of his own ships, partly of a squadron furnished to him by Sparta--had appeared off the coast and threatened a landing. Cyrus thus crossed the most difficult and dangerous of all the passes that separated him from the heart of the Empire, without the loss of a man.