401 BC

By place

Persian empire

• Cyrus the Younger uses a quarrel with Tissaphernes over the Ionian cities as a pretext for gathering a large army and also pretends to prepare an expedition to Pisidia, in the Taurus Mountains. Cyrus starts out with about 20,000 men, of whom around 10,000 are Greek mercenaries. When he reaches the Euphrates River at Thapsacus, he announces that he is marching against Artaxerxes II. He advances unopposed into Babylonia; but Artaxerxes, warned at the last moment by Tissaphernes, hastily gathers an army. The two forces meet in the Battle of Cunaxa, north of Babylon, where Cyrus is slain.

  Greece

• The Greek mercenaries fighting for Cyrus are left stranded after Cyrus' defeat. They fight their way north through hostile Persians, Armenians, and Kurds to Trapezus on the coast of the Black Sea under Xenophon, who becomes their leader when the Persian satrap, Tissaphernes has Clearchus of Sparta and the other senior Greek captains captured and executed by Artaxerxes.
• Agesilaus II becomes king of Sparta on the death of his stepbrother Agis II.

  China

• Zhou an wang becomes King of the Zhou Dynasty of China.

  By topic

Literature

• Sophocles' tragic play Oedipus at Colonus is performed posthumously. It is produced by his grandson at the Festival of Dionysus in Athens.