Query: When was the Battle of Cannae?
Context: Tension between Macedon and Rome increased when the young king of Macedon, Philip V harbored one of the chief pirates, Demetrius of Pharos (a former client of Rome). As a result, in an attempt to reduce Roman influence in the Balkans, Philip allied himself with Carthage after Hannibal had dealt the Romans a massive defeat at the Battle of Cannae (216 BC) during the Second Punic War. Forcing the Romans to fight on another front when they were at a nadir of manpower gained Philip the lasting enmity of the Romans; the only real result from the somewhat insubstantial First Macedonian War (215–202 BC).