 After these expeditions returned home, Brennus urged and persuaded them to mount a third united expedition against central Greece, led by himself and Acichorius.A Greek coalition made up of Aetolians, Boeotians, Athenians, Phocians, and other Greeks north of Corinth took up positions at the narrow pass of Thermopylae, on the east coast of central Greece.During the initial assault, Brennus' forces suffered heavy losses.