The Roman leadership began to worry that Perseus would destroy Roman political control in Greece and restore former Macedonian sovereignty over Greek states. King Eumenes II of Pergamon, who hated Macedonia, accused Perseus of trying to violate laws of other states and conditions of peace between Macedonia and Rome. The Romans were afraid for the balance of power in Greece and declared a new war with Macedonia. Perseus won the first struggle: the Battle of Callicinus, where he faced the army of Publius Licinius Crassus. The king offered a peace treaty to the Romans, which was refused. The Romans had problems with discipline in their army, and Roman commanders could not find a way to successfully invade Macedonia.