The Battle of Chaeronea is fought in 338 BCE, near the city of Chaeronea in Boeotia, between the forces of Philip II of Macedon and an alliance of Greek city-states including Athens and Thebes.

The battle is the culmination of Philip's campaign in Greece (339–338 BCE) and results in a decisive victory for the Macedonians.Philip had brought peace to a war-torn Greece in 346 BCE, by ending the Third Sacred War, and concluding his ten-year conflict with Athens for supremacy in the north Aegean, by making a separate peace.

Philip's much expanded kingdom, powerful army and plentiful resources now make him the de facto "leader of Greece".

To many of the fiercely independent Greek city-states, Philip's power after 346 BCE is perceived as a threat to their liberty, especially in Athens, where the politician Demosthenes leads efforts to break away from Philip's influence.

When, in 340 BCE, Athens forms an alliance with a city Philip is then besieging, he finally loses patience, and declares war on the Attic state.

In summer 339 BCE, Philip therefore leads his army into Greece, prompting the formation of an alliance of Greek states opposed to him, led by Athens and Thebes.After several months of stalemate, Philip finally advances into Boeotia in an attempt to march on Thebes and Athens.

Opposing him, and blocking the road near Chaeronea, is the allied Greek army, similar in size and occupying a strong position.

Details of the ensuing battle are scarce, but after a long fight, the Macedonians crush both flanks of the allied line, which then dissolves into a rout.The battle has been described as one of the most decisive of the Ancient World.

The forces of Athens and Thebes weare destroyed, and continued resistance is impossible; the war therefore comes to an abrupt end.

Philip is able to impose a settlement upon Greece, which all states accept, with the exception of Sparta.

The League of Corinth, formed as a result, makes all participants allies of Macedon and each other, with Philip as the guarantor of the peace.

In turn, Philip is voted as strategos (general) for a pan-Hellenic war against the Persian Empire, which he had long planned.

However, before he is able to take charge of the campaign, Philip is assassinated, and the kingdom of Macedon and responsibility for the war with Persia passesi nstead to his son Alexander.