During the Trojan War, Achilles, grieving the death of his closest companion Patroclus, organized a grand funeral in his honor.

After a fierce quarrel with Agamemnon, Achilles withdrew from the Achaean army and refused to fight. This absence played directly into the hands of the Trojans, who launched a powerful offensive and pushed the Achaeans back to the shore.

Distressed by the Achaean losses and the stubborn stance of Achilles, Patroclus entered the battlefield wearing Achilles’ armor and bearing his weapons. But in a clash with Hector, the Trojan prince, Patroclus was slain.

The news of Patroclus’ death was delivered to Achilles by Antilochus, son of Nestor.

"A cloud of black grief enveloped Achilles.
He took ashes in both hands,
poured them over his head, defiling his fair face.
Then he threw himself to the ground,
stretched out in the dust,
and tore at his hair with his hands."

(Il. XVIII, 1)

That night, the spirit of Patroclus appeared to Achilles, asking for his funeral rites to be performed. Achilles, weeping, responded:

“Why have you come to me, my dear friend?

Why say such things?

Know that I shall do all you ask of me.

Come closer, let us embrace one another,

let us grieve together, even just for a moment.”

So he spoke and stretched out his hands—

but he could grasp nothing.

The soul had vanished like smoke,

slipping down to the underworld, whistling as it went.”

(Il. XXIII, 94 ff.)

With weapons forged by the god Hephaestus at the request of his mother Thetis, Achilles returned to battle. He avenged Patroclus by slaying Hector in single combat.

After the battle, true to his word, Achilles honored his friend with a grand funeral ceremony and games, celebrating the life of Patroclus and mourning his loss with the entire Achaean army.