In which book of the Iliad does Patroclus die?

Patroclus dies in Book 16 of Homer’s Iliad.

Patroclus enters the battle wearing Achilles’ armor after the Trojan attack threatens to burn the Greek ships. Achilles allows him to lead the Myrmidons, hoping the disguise will terrify the Trojans and drive them away. Patroclus succeeds brilliantly at first, killing many enemies and even defeating Sarpedon, Zeus’s son and a major Trojan ally.

Patroclus then goes beyond Achilles’ instructions and pursues the Trojans toward Troy. The god Apollo strikes and disorients him, Euphorbus wounds him, and Hector delivers the fatal blow. Hector strips Achilles’ armor from the fallen warrior, setting up the chain of revenge that drives the rest of the epic.

The death occurs in Book 16, often called the Patrocleia, but its consequences dominate Books 17 and 18. News of Patroclus’s death breaks Achilles’ anger toward Agamemnon and redirects his fury toward Hector.