Battle of Chaeronea (338 BC): Philip II Conquers Greece

The Battle of Chaeronea, fought in Boeotia in central Greece in the summer of 338 BC, was the decisive victory of King Philip II of Macedon over an alliance led by Athens and Thebes. The 18-year-old Alexander, the future Alexander the Great, commanded the Macedonian cavalry. The battle effectively ended the independence of the classical Greek city-states and opened the way for the Macedonian invasion of the Persian Empire.

Background: the rise of Macedon

When Philip II became king in 359 BC, Macedon was a troubled kingdom on the northern edge of the Greek world. In two decades he reorganised its army around the phalanx, a deep formation of infantry armed with the sarissa, a pike about 5 to 6 metres long, supported by heavy cavalry known as the Companions. He used war, bribery, marriage alliances and diplomacy to expand into Thrace, Thessaly and the coastal cities of the northern Aegean.

Athens, led in its resistance by the orator Demosthenes, saw Philip as a threat to its grain supply from the Black Sea and to its influence in the north. The Peace of Philocrates of 346 BC brought a pause, but tension grew again after Philip besieged Perinthus and Byzantium in 340 BC and seized an Athenian grain fleet.

The immediate cause was a religious conflict, the Fourth Sacred War. In 339 BC the Amphictyonic Council, which oversaw the sanctuary of Delphi, asked Philip to punish the city of Amphissa. Philip marched south and occupied Elatea, a town controlling the route into Boeotia. In Athens, Demosthenes persuaded the assembly to seek an alliance with its old rival Thebes, and the Thebans agreed.

The armies

Diodorus says that Philip had more than 30,000 infantry and at least 2,000 cavalry. The allied army, made up chiefly of Athenians and Boeotians with contingents from Corinth, Achaea, Megara and other states, was probably of similar or slightly larger size. Modern estimates for each side usually fall between 30,000 and 35,000 men.

The allies were led by several commanders, including the Athenian generals Chares, Lysicles and Stratocles and the Theban Theagenes. They lacked a single overall commander. The Macedonian army, by contrast, was a professional force that had fought almost continuously for 20 years under one king.

The allies took up a strong position across the plain near Chaeronea, between the hills to the south and the Cephissus river to the north. The Athenians held the left wing, various allies the centre and the Thebans the right, with the elite Theban Sacred Band at the end of the line beside the river.

What happened

The ancient accounts are short and partly contradictory, so the course of the battle is reconstructed with some uncertainty. The most widely accepted version draws on Diodorus, Plutarch and the later military writer Polyaenus.

Philip commanded the Macedonian right, facing the Athenians, while Alexander led the left with senior generals beside him. According to Polyaenus, Philip ordered his right wing to fall back slowly. The inexperienced Athenians pressed forward eagerly, and the allied line stretched and opened gaps as other units moved to keep contact.

At that moment Alexander attacked on the left. Diodorus says he was the first to break the enemy line. The Thebans and the Sacred Band, cut off and surrounded, fought to the end. Philip then turned his own wing and drove the Athenians from the field. Demosthenes, who served in the ranks as a hoplite, escaped with the fleeing army, a fact his political opponents never let him forget.

Losses

Diodorus reports that more than 1,000 Athenians were killed and at least 2,000 taken prisoner. Theban losses were also heavy, though no reliable total survives. The Sacred Band, said to have numbered 300 men, was destroyed. Macedonian casualties are not recorded.

When the lion monument over the Theban grave was excavated in 1879-1880, archaeologists found the remains of 254 men laid out in seven rows. Many scholars identify them as members of the Sacred Band, which would mean that almost the entire unit fell. A large burial mound in the plain, excavated in the early 20th century, has been interpreted as the grave of the Macedonian dead, although this identification is debated.

Key people

• Philip II of Macedon (c. 382-336 BC): king who turned Macedon into the leading power in Greece.
• Alexander (356-323 BC): Philip’s son and heir, who won his first great military distinction here.
• Demosthenes (384-322 BC): Athenian orator who built the alliance against Philip and delivered the funeral speech for the Athenian dead.
• Chares and Lysicles: Athenian generals. Lysicles was later condemned to death in Athens for the defeat.
• Theagenes: Theban commander, killed in the battle according to later tradition.

Consequences

Philip treated the defeated states differently. Thebes, which had broken an earlier alliance with him, was punished: a Macedonian garrison was placed on the Cadmea, its citadel, and pro-Macedonian exiles returned to power. Athens received surprisingly mild terms through the Peace of Demades. Philip released the Athenian prisoners without ransom and sent the ashes of the Athenian dead home with an escort that included Alexander and the general Antipater.

In 337 BC Philip summoned delegates of the Greek states to Corinth. There he created a federation now called the League of Corinth, which guaranteed peace among its members and made Philip its leader (hegemon). The league declared war on Persia, presented as revenge for the Persian invasions of the 5th century BC. Only Sparta stayed outside.

Philip did not live to lead the campaign. He was assassinated at Aegae in 336 BC, and Alexander inherited both the throne and the war, crossing into Asia in 334 BC.

Myths and facts

Myth: Chaeronea ended Greek freedom overnight. In practice the city-states kept their own laws, assemblies and coinage, and several revolted in the following years. What changed was that real power over war and foreign policy now lay with the Macedonian king.

Myth: the feigned retreat is a certain fact. The story of Philip’s deliberate withdrawal comes mainly from Polyaenus, who wrote some five centuries later. Many historians accept it as plausible, but the surviving evidence does not allow a detailed, certain reconstruction of the fighting.

Legacy and memory

Chaeronea is commonly treated as the moment when the age of independent Greek city-states, which had flourished since the Persian Wars, gave way to Macedonian and later Hellenistic monarchies. Athens and Thebes continued to exist and even to rebel, as Thebes did in 335 BC and Athens in 323 BC, but they never again shaped Greek politics on their own terms.

The Lion of Chaeronea, a marble lion several metres high, was set up over the Theban grave, probably by the Thebans themselves; the traveller Pausanias described it in the 2nd century AD. It was found broken in 1818, reassembled and re-erected in 1902. The town of Chaeronea was also the birthplace of Plutarch, whose biographies preserve much of what is known about the battle.

Timeline

• 359 BC: Philip II becomes king of Macedon and begins reforming the army.
• 346 BC: The Peace of Philocrates between Athens and Macedon.
• 340 BC: Philip besieges Perinthus and Byzantium and seizes an Athenian grain fleet.
• 339 BC, autumn: Philip occupies Elatea; Athens and Thebes form an alliance.
• 338 BC, 2 August (traditional date): Macedonian victory at Chaeronea.
• 337 BC: The League of Corinth is founded with Philip as hegemon.
• 336 BC: Philip is assassinated at Aegae; Alexander becomes king.

Why it matters

Chaeronea decided that Macedon, not Athens or Thebes, would lead the Greek world. It gave Philip the unified Greek backing he wanted for a war on Persia and launched the career of Alexander, whose conquests transformed the eastern Mediterranean and western Asia.