When the Peloponnesians were outvoting him, Themistocles secretly left the assembly, and sent a man by boat to the Median fleet after ordering him what to say. His name was Sicinnus, and he was Themistocles' servant and his sons' attendant. Later Themistocles enrolled him as a Thespian, when the Thespians were adopting citizens, and made him wealthy with money.

He now came by boat and said to the generals of the barbarians, “The Athenian general has sent me without the knowledge of the other Hellenes. He is on the king's side and prefers that your affairs prevail, not the Hellenes'. I am to tell you that the Hellenes are terrified and plan flight, and you can now perform the finest deed of all if you do not allow them to escape.

They do not all have the same intent, and they will no longer oppose you. Instead you will see them fighting against themselves, those who are on your side against those who are not.” After indicating this to them he departed.