Livy, a Roman historian of the late first century BC, wrote a long History of Rome from the city’s founding. This is Book 33. In the last book, Titus Quinctius Flamininus, young for a consul — one of two officials elected to run Rome for a year — was still fighting Philip V of Macedon in Greece, peeling allies from the king and clearing the ground for a battle in Thessaly, in northern Greece.

At Cynoscephalae, the Dogs’ Heads — broken hills in Thessaly — the Macedonian phalanx, a dense wall of long spears, cannot keep its front. Flamininus’s legions, Rome’s army units, find the seams and cut Philip’s army to pieces. Macedon keeps a throne and loses its hold over Greece. At the Isthmian Games, a festival near Corinth, a herald proclaims the Greeks free; the roar is aimed at Philip’s garrisons as much as at joy. The Aetolians, a Greek league that fought with Rome, already dislike the settlement. Flamininus plays the friend of Greece on a Roman brief. What follows is whether that freedom can live with its new arbiter.