Brennus (3rd century BC)

Brennus (or Brennos) (died 279 BC) was one of the leaders of the army of the Gallic invasion of the Balkans, defeated the assembled Greeks at Thermopylae, and is popularly reputed to have sacked and looted Delphi, although the ancient sources do not support this.

In 280 BC a great army, comprising about 85,000 warriors, coming from Pannonia and split in three divisions, marched south in a great expedition to Macedonia and central Greece. The division led by Brennus and Acichorius moved against the Paionians.

Some writers suppose that Brennus and Acichorius are the same person, the former being only a title and the latter the real name.

The other two divisions were led by Cerethrius and Bolgios, moving against the Thracians and Triballi, and against the Macedonians and Illyrians, respectively.

Brennus is said to have belonged to an otherwise unknown tribe called the Prausi. These Gauls had settled in Pannonia because of population increases in Gaul, and sought further conquests.

The army was initially led by Cambaules, who led them as far as Thrace, where they stopped. When they decided to advance again in 279 BC, they split their forces into three divisions. One division was led by Cerethrius against the Thracians and Triballi; another by Bolgios against the Macedonians and Illyrians; and the third against Paionia by Brennus and Acichorius. Bolgios' expedition inflicted heavy losses on the Macedonians and killed their king, Ptolemy Keraunos, but was repulsed by the Macedonian nobleman Sosthenes. Brennus' contingent then attacked Sosthenes and defeated him, and proceeded to ravage the country. After these expeditions returned, Brennus urged a united, and potentially lucrative, attack on Greece, led by himself and Acichorius. The army numbered 152,000 infantry and 24,400 cavalry. Pausanias describes how they used a tactic called trimarcisia, where each cavalryman was supported by two mounted servants, who could supply him with a spare horse if he was dismounted, or take his place in the battle if he was killed or wounded, so the actual number of horsemen was in fact 61,200.

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