409 BCCenturies: 6th century BC - 5th century BC - 4th century BC
- Alcibiades recaptures Byzantium for Athens.
- Athenian expedition of Thrasyllus fails to capture Ephesus.
- Pausanias succeeds his father Pleistoanax as king of Sparta
- Hannibal Mago leads a Carthaginian expedition to Sicily in an attempt to gain control of the island
- Pleistoanax, king of Sparta