The Ionian war was more complex than any previous war in which Greeks had fought one another. Various factors contributed to its complexity. One of them was the uneasy partnership between Peloponnesians and Persians, which seldom functioned to the complete satisfaction of the former and was at times almost in abeyance. Other factors were the oligarchical revolution at Athens, which nearly plunged the Athenians into civil war, and the chameleon-like behaviour of Alcibiades, who within a brief period lent his services first to Sparta, then to Persia, and finally to Athens, though at all times serving primarily his own interests. Yet another factor was the multiplicity of Greek states directly or indirectly involved in the war. In addition to those of the Greek homeland and of Italy and Sicily which supplied contingents to the Peloponnesian expeditionary forces in Asia, all the members of the Delian Confederacy included at any time in the Ionian, Hellespontine, and Carian districts, numbering more than 150, must have been affected to some extent by the war, though only a fraction of them played an active part in it. The aim of this paper is to consider the attitude of Asiatic Greek cities towards the war and the extent of their involvement in it.