Livy wrote his History of Rome in the late first century BC. Book 40 is set in the 180s BC. Rome is still a republic: a city run by a senate and elected officials, not a king. The last book left Italy after Hannibal: a secret cult hunted, and a people arguing with itself about what victory brought home.

King Philip V of Macedon — the kingdom north of Greece — lives his last years as a palace tragedy. His sons Perseus and Demetrius cannot share a future. Demetrius’s friendships with Romans become a death sentence. Philip reforms and rages; the kingdom looks strong and rotten. Greek cities carry complaints to Rome. Rome watches because a revived Macedon would undo the freedom it proclaimed for the Greeks. By the end Perseus has the throne, and the third Macedonian war is already an inheritance.