The island of Aegina and the city of Athens go to war. The island has earned the enmity of Athens by earlier submitting to the Persians. The Spartan King, Leotychidas, tries unsuccessfully to arrange a truce in the war.
The Athenian Archonship becomes elective by lot from all the citizens, an important milestone in the move towards radical Athenian democracy. There are nine archons and a secretary. Three of the archons have special functions: the basileus, or sovereign; the polemarch (originally a military commander); and the archon eponymous (chief magistrate), who gave his name to the year.
Reign of Darius I.
- Gorgias, Greek philosopher (approximate date) (d. c. 376 BC)