Battle of Chaeronea (338 BCE)

In August 338 BC, near the town of Chaeronea in Boeotia, the Macedonian king Philip II defeated the combined armies of Athens, Thebes and their allies. The victory left no Greek power able to resist him and allowed Philip to impose a settlement on almost all of Greece through the League of Corinth. It is often counted among the most decisive battles of the ancient world, and it was also the first major command of his eighteen-year-old son, the future Alexander the Great.

After coming to the throne in 359 BC, Philip rapidly strengthened Macedon and expanded it into Thrace and Chalkidiki while Athens and Thebes were absorbed in other conflicts. By 346 BC he had ended the Third Sacred War on his own terms and made peace with Athens through the Peace of Philocrates. Many Greeks, however, saw him as a threat to the independence of their cities. In Athens the orator Demosthenes led a party determined to undo the peace, and when Athens allied with Byzantium, which Philip was besieging, Philip declared war.

A dispute over sacred land near Delphi gave Philip a pretext to bring his army south in 339 BC. Thebes had blocked the main route by seizing Nicaea, near Thermopylae, but Philip used a side road and slipped into central Greece, where he restored the Phocians and gained a base at Elatea. The news caused panic in Athens. Demosthenes persuaded the Athenians to seek an alliance with Thebes, their old rival, and the Thebans agreed despite Philip's own embassy. Several months of manoeuvre and skirmishing followed, of which little is known. In August 338 BC Philip finally marched down the main road into Boeotia, where the allied army was waiting.

According to Diodorus, Philip had about 30,000 infantry and 2,000 cavalry, a figure most modern historians accept. Philip led the right wing; Alexander, supported by experienced generals, commanded the left. No ancient source gives reliable figures for the Greek alliance, but its army is thought to have been of roughly similar size. The Athenians held the left of the line, the Thebans the right, and contingents from Corinth, Megara, Achaea and other states the centre. Their line, anchored on high ground on one side and a river on the other, was a strong defensive position.

The only formal account, by Diodorus, says the fight was long and evenly balanced until Alexander broke through the allied line and routed its right wing, while Philip drove off the left. Anecdotes preserved by later writers suggest that Philip may have pulled his wing back, drawing the inexperienced Athenians forward out of formation before turning on them. Whether these stories are reliable is uncertain. According to Plutarch, Alexander was the first to break into the ranks of the Theban Sacred Band, an elite unit of 300 that was almost entirely destroyed. Diodorus says more than 1,000 Athenians were killed and 2,000 captured, with Theban losses on a similar scale. Excavations beneath the Lion of Chaeronea monument found the remains of 254 men, generally taken to be members of the Sacred Band.

Philip did not set out to conquer the cities. He wanted Greece stable and allied behind him for a planned war against the Achaemenid Empire. Thebes was punished with a garrison and the exile of its leaders, while Athens was treated leniently, perhaps because Philip hoped to use its fleet. In 337 BC he organised the League of Corinth, which every major state except Sparta joined. Its members became allies of Macedon and of each other, and the league voted Philip commander of a war against Persia.

Philip was assassinated in 336 BC before he could lead the campaign. Alexander inherited both the kingdom and the war, and between 334 and 323 BC conquered the whole Persian Empire.

Our 400 BCE map shows the Greek city-states before Macedon's rise, and our 323 BCE map shows the Macedonian Empire at Alexander's death. The battlefield lies in modern Greece.