Photo cover: The Dying Gaul, or The Capitoline Gaul, a Roman marble copy of a Hellenistic work of the late 3rd century BC Capitoline Museums, Rome. The original may have been commissioned at some time between 230 and 220 BC by Attalus I of Pergamon to celebrate his victory over the Galatians, the Celtic (or Gaulish) people.

Text by Manolis Chatzimanolis

By the mid-4th century B.C., Celtic tribes had already settled in the middle Danube region, where they had also encountered Alexander the Great during his campaign in the northern Balkans in 335 B.C. Hearing stories about the legendary wealth of Greek sanctuaries and having increased their numbers with refugees expelled by the Romans from northern Italy in 284 B.C., three Gallic hordes—together with civilians totaling around 150,000¹—turned south in 279 B.C. for new conquests. (The numbers provided by the historians (Pausanis, Diodorus, Justinus) are clearly somewhat exaggerated; however, they effectively emphasize the critical danger faced by the Greeks and the tremendous destruction inflicted upon the Gauls.). One group eventually headed to and settled in Thrace, while two others, led by Bolgios and Brennus, invaded Greece via the valleys of the Aoos and Axios rivers, respectively.

After defeating the Macedonian army,in which the Macedonian king Ptolemy Keraunos was killed, and plundering Macedonia relentlessly throughout the summer, they crossed Thessaly in the autumn, heading toward Central Greece and Delphi, with the apparent intention of sacking the famous sanctuary of Apollo. After successfully bypassing the Greek forces guarding the Spercheios River, they were halted at Thermopylae, where a force of about 20,000 Greeks—6,500 hoplites from Sparta, Tegea, Mantineia, Orchomenus, other Arcadian cities, Mycenae, Phlius, Corinth, Thespiae, Thebes, Phocis, plus tens of thousands from Locrians and Aetolians, and 500 cavalry from Boeotia, 500 cavalry from Athens, plus 1,000 Athenian infantry.—was stationed.

The Greeks maintained order in their phalanx, deploying javelins, arrows, and slings. Cavalry proved ineffective due to narrow and slippery terrain. Many Celts were wounded or lost in the marshes, while the Athenians, using ships and missile fire, held the coastline. Casualties among the Celts were severe, nearly matching those sustained at the height of the battle.² Having failed to storm the pass head-on, the Celts decided to adopt an indirect strategy to divide the Greek forces.

Knowing that many Aetolians were among those guarding Thermopylae, they planned for part of their army to strike Aetolia, forcing the Aetolians to abandon the pass and rush to defend their homeland. Thus, one-third of their army, 40.000 infantry and 8.000 cavalrymen, under the chieftains Orestorius and Combutus, set out at night. After a march of roughly twelve hours, following the Spercheios River to modern Ypati, they moved into the slopes of Mount Oeta and, following the Giona range and the valley of the Dafnos River, reached the Aetolian city of Kallion, which they found undefended. The defenseless settlement was looted with unprecedented brutality and leveled. The entire male population was slaughtered; many of the Kallians’ women committed suicide to avoid abuse by the Gauls, and there were even cases of infant cannibalism.³

News of the Gallic invasion and the destruction of Kallion spread throughout Aetolia and beyond, provoking an immediate reaction in Greece. While the Gauls ravaged the surrounding area, the Aetolians gathered all the men and women (“.. The women also joined the expedition voluntarily, showing even greater fury against the Gauls than the men..”) , capable of bearing arms in their capital Thermon, and a force of 1,000 soldiers from Patras came to their aid. Together with the 7,000 Aetolians returning from Thermopylae in a fury, the forces of the Confederacy under the Aetolian leader Eurydamus likely numbered 16,000–20,000 combatants.

With the risk of encirclement in the rugged terrain of Aetolia evident, the Celts decided to retreat to their camp in the Spercheios plain. During their withdrawal, they were continuously harassed by Aetolian skirmishers following closely behind. ”..positioned along the entire road, hurled javelins at the barbarians, and since the latter carried shields unsuited to local fighting, few missiles missed their mark. They easily avoided pursuit, and when the enemy turned back from the chase, they pressed upon them again with renewed vigor..” Simultaneusly, their rearguard was smashed in a pitched battle in which Achaean soldiers distinguished themselves. Eventually, the Celts were trapped on the border of the present-day Evrytania and Phthiotis regions, where the returning Aetolians awaited them with murderous intent.

At the same time, events unfolded for the Greeks stationed at Thermopylae. A mountain path across Mount Oeta offered Brennus a route to outflank them, as once used by the Persians against Leonidas. Brennus advanced with a selected force. Fog delayed detection, allowing him to surprise the Phocian guards, though they resisted and escaped, warning their allies. The Athenians evacuated the Greek army by sea before encirclement. Brennus immediately marched toward Delphi, while Aetolians relentlessly harassed his forces, attacking stragglers, seizing supplies, and significantly slowing his advance.

The Greeks assembled at Delphi opposed Brennus and his army. At the beginning of the battle, especially the troops around Brennus—who were the tallest and bravest of the Gauls—still held their ground through sheer determination, though they were being struck from all sides and suffering no less from the cold, particularly the wounded. When Brennus himself was wounded, they carried him fainting from the battlefield. “..After much fighting, losing tens of thousands of his soldiers there, Brennus himself was struck three times. Weighed down and close to death, he gathered his people and advised the Gauls to kill him and all the wounded, burn the wagons, and return home; he appointed Cichorius as king. Brennus, taking much unmixed wine, killed himself..”⁴

The ensuing slaughter was undoubtedly horrific: of the 40,000 Gauls who invaded Aetolia, only 18,000 managed to reach the Spercheios, while the rest were left to rot unburied where they fell. In the following centuries, the location came to be known as Kokkalia (“κόκαλο” is the word for bone in Greek), as local peasants continued to find, even into the early 20th century, bones, iron helmets, and arrowheads—remnants of a ferocious battle that had taken place more than 2,000 years earlier.

Sources:

Pausanias (2nd c. AD) — Description of Greece (10.19–23)

Diodorus Siculus (1st c. BC) — Library of History (Book 22)

Justin (4th c. CE) — Epitome of the Philippic History of Pompeius Trogus (Book 24)

H. D. Rankin (1987/1996). Celts and the Classical World. Routledge

Dáithí Ó hÓgáin (2002). The Celts: A History. Boydell Press

Footnotes

1. The assembled army numbered 150.000 of infantry, with an additional two thousand, and the cavalry numbered four hundred and twenty thousand. These were the effective number of cavalry in action, though the true count was two hundred and sixteen thousand: for each cavalryman there were two attendants, who themselves were skilled and equipped with horses in the same way. Pausanias,Description of Greece, 10.19.9-11. ↩︎
2. The Celts, however, advanced with rage and fury, without any reasoning, like wild beasts; they were undeterred by blows from axes or swords, nor by arrows and javelins, until their life left their bodies. When wounded, they lifted the spears that had been thrown at them, attacked the Greeks again, and fought using their weapons with their hands. Pausanias, Description of Greece, 10.21.1-4. ↩︎
3. Pausanias, Description of Greece, 10.22.4. ↩︎
4. Diodorus Siculus (1st c. BC) — Library of History (Book 22.9.1-9.) ↩︎