[2][3] After the defeat of the Second Persian invasion of Greece in 479 BCE, Gongylos was forced to flee and take refuge in the Achaemenid Empire.
[4] Gongylos was one of the several Greek aristocrats who took refuge in the Achaemenid Empire following reversals at home, other famous ones being Hippias, Demaratos, and Themistocles.
[3] In general, those were generously welcomed by the Achaemenid kings, and received land grants to support them, and ruled over various cities of Asia Minor.
[3] According to Xenophon (Anabasis, 7.8.8-17), when he arrived in Mysia in 399, he met Hellas, the widow of Gongylos and probable daughter of Themistocles,[5] who was living at Pergamon.
[4] However, by the mid-4th century BCE, the Achaemenid satrap Orontes again allowed the people of Pergamon to settle on the acropolis of their city.