Who was the leader of the Lycians who fought for the Trojans?

Sarpedon was the leader of the Lycians who fought for the Trojans in the Trojan War.

In Homer's Iliad, Sarpedon arrives from Lycia with his cousin Glaucus and commands a powerful allied force. He is one of Troy's most important supporters, even though he is not Trojan by birth. During the fighting, he rebukes Hector for allowing Troy's allies to bear too much of the battlefield burden.

Sarpedon is also portrayed as a son of Zeus and Laodamia, making him a mortal hero with divine ancestry. In Book 16, he is killed by Patroclus while attacking the Greek defenses. Zeus considers rescuing his son, but Hera warns that interfering would provoke the other gods. After Sarpedon's death, Glaucus rallies the Lycians and Trojans to protect his body.

A common mix-up is Glaucus, who was Sarpedon's fellow commander and cousin, not the single leader named in the question. Later myths also give differing genealogies for Sarpedon.