The Foreign War (Greek: Ξενικὸς Πόλεμος Xenikos Polemos) was fought between the forces of Knossos with the help of mercenaries under the ousted Phocian leader Phalaikos and the forces of Lyttos who received help from the Spartans (who were founders of their city) under their King Archidamus III. The war took place in 346 BC.
Knossos wanted to strengthen their hegemony of Crete but received opposition from the Lyttians. In response Knossos employed foreign mercenaries under the former Phocian leader Phalaikos. In 346, Knossos declared war against Lyttos. Phalaikos who was given command of the forces of Knossos and of the mercenaries was about to seize Lyttos when the Lyttians asked the Spartans for help. The Spartans under King Archidamus rushed to help the Lyttians. The Spartans came in time to save Lyttos and defeat Phalaikos. Phalaikos then turned against Kydonia. This decision proved fatal for Phalaikos who was slain in the siege and his army was destroyed.
This war proved to be a turning point in Cretan history since it was the first time foreign forces had come to Crete and interfered in Cretan affairs.