Perseus wins the first struggle with Rome: the Battle of Callicinus, near Larissa, where he faces the army of the consul Publius Licinius Crassus.

The battle is notable for the prevalent role of cavalry and light infantry as a combined 'task force'.

Satisfied with the defeat of most of the deployed Roman forces, Perseus takes his general Euander's advice and has his forces retire before engaging the remaining heavy infantry.

His initial success against the Roman army in Thessaly in 171 does not alter the massive imbalance of power; the Romans again refuse the king's offer to negotiate.

Attalus of Pergamon, now around fifty, remains a loyal assistant to his brother Eumenes, commanding the Pergamene forces that are fighting beside the Romans in Greece.