The reasoning behind the Sacred Band was that lovers would fight more fiercely and more cohesively at each other's sides than would strangers with no homoerotic bonds. The Sacred Band was 150 pairs of lovers, a total of three hundred men led them to their gallant end on the blood-drenched field of Chaeronea, in 338 B.C.E.
Plutarch chronicled their exploits. Gorgidas, around 378 BC first established the Sacred Band by shoosing couple from his army. Plato had first proposed such a troop in the Symposium: "If there were only some way of contriving that a state or an army should be made up of lovers and their loves, they would be the very best governors of their own city, abstaining from all dishonour, and emulating one another in honour; and when fighting at each other's side, although a mere handful, they would overcome the world. For what lover would not choose rather to be seen by all mankind than by his beloved, either when abandoning his post or throwing away his arms? He would be ready to die a thousand deaths rather than endure this. Or who would desert his beloved or fail him in the hour of danger? The veriest coward would become an inspired hero, equal to the bravest, at such a time; Love would inspire him.”
Plutarch in his Life of Pelopidas said this was Gorgidas' inspiration: “Since the lovers, ashamed to be base in sight of their beloved, and the beloved before their lovers, willingly rush into danger for the relief of one another.”
The Sacred Band was at first dispersed throughout the front ranks of the regular infantry, with the idea that they would inspire valour, but they were latter arrayed as a unit in order to make their gallantry more conspicuous.
After Thebes was conquered in the Peloponnesian War in 404, bands of guerilla troops fought with the Spartan troops, becoming fierce warriors. Pelopidas recaptured a Theban fortress in 379 and he assumed the command of the Sacred Band in which he fought alongside his former lover General Epaminondas.
The Sacred Band under Pelopidas fought the Spartans in Tegyra, vanquishing an army that was at least three times their number.
The Sacred Band was also responsible for the victory of Leuctra in 371 BC, called by Pausanias the most decisive battle ever fought by Greeks against Greeks. Leuctra established Theban independence from Spartan rule, and laid the groundwork for the expansion of Theban power.
The Sacred Band was eventually destroyed by Philip II of Macedon, who had been held as a hostage in Thebes, and had learned his military tactics there. The remainder of the Theban army fled when faced with the overwhelming forces of Philip and his son Alexander, but the Sacred Band, surrounded, held their ground and died where they stood. Only forty six were taken alive.
Plutarch records the words of Philip, touring the field after the battle in his Life of Pelopidas:“lying all where they had faced the long spears of his phalanx, with their armour, and mingled one with another, he was amazed, and on learning that this was the band of lovers and beloved, shed tears and said, ‘Perish miserably they who think that these men did or suffered aught disgraceful!” Philip buried their bodies with honor, setting up the Lion of Chaeronea over them. The grave was excavated in 1881, confirming Plutarch's account.