Boeotia
- Koroneia, Boeotia
- Larymna, Boeotia
- Mykalessos, Boeotia
- Orchomenos, Boeotia
- Tanagra, Boeotia
- Thebes
- Thespiai, Boeotia
The Battle of Thermopylae. Soldiers from Sparta, Mantinea, Tegea, Orchomenos (Arkadia), Corinth, Phlious, Thespiai, Phokis, Opuntian Lokris, and other cities are overrun by the Persians at a huge cost.
Thebes takes Herakleia Trachineia from Sparta and installs the Trachinians and Oetaians.
July
Eresos, Byzantion, Chios,Mytilene, Methymna, Rhodes, Thebes, Korkyra, Eretria, Kios, Samos, Naxos, Andros, Myrina (Lembos), Hephaistia, Imbros, and Thasos join the Second Athenian League, reaffirming its alliance with Athens in response to the growing threat of Persian interference and internal Greek conflicts.
The Theban general Pelopidas intervenes in Macedonian affairs, leading an expedition to secure Alexander II‘s position. However, Alexander is forced to agree to a treaty that acknowledges Theban influence and sends his brother Philip II to Thebes as a hostage.
July
The Theban Pelopidas is sent to negotiate with Alexander of Pherai, who throws him in prison.
Thebes defeats Alexander of Pherai at the Battle of Cynoscephalae, but their general Pelopidas is killed.
July 4
With Theban power down after the death of Epaminondas, Alexander of Pherai takes Tinos and sells the inhabitants as slaves, then besieges Peparethos. Athens defeats Alexander near Sounion and relieves Peparethos. Alexander then plunders Piraios.
The Aetolian League, Athens, and Thebes revolt against Macedon after the death of Philip II.
Alexander the Great demolishes Thebes after a rebellion.
326 BCE
Demetrios Poliorketes and Antigonos II take Thebes after a siege. Huge siege engines are used to break its walls.