Last king of Macedonia, eldest son of Philip V. He had his brother Demetrius killed, and thus cleared his way to the throne in 179. War broke out with Rome in 171 B.C. when P. Licinius Crassus was sent to attack him. Perseus defeated Crassus at Callinicus in Thessaly, but in 168 he was annihilated at Pydna by L. Aemilius Paulus. He was led in triumph through Rome, and died in captivity at Alba Fucens.