217 BC was one of the worst years in Roman history, and one of the most consequential. Rome entered it reeling from the previous December's defeat at the Trebia, where Hannibal had routed Sempronius Longus. The new consuls were Gaius Flaminius and Gnaeus Servilius Geminus. Flaminius, a populist long at odds with the senatorial aristocracy, took the field under a cloud of ill omens. In the spring, Hannibal crossed the Apennines via the flooded Arno marshes. This four-day slog cost him most of his remaining elephants and the sight in one eye, yet he emerged into Etruria behind the Roman position.

What followed on June 21 was less a battle than an annihilation. At Lake Trasimene, Hannibal concealed his army in the morning fog above the road and let Flaminius march directly into the trap. In roughly three hours, around 15,000 Romans were killed, including the consul himself, and thousands more captured. Rome's response was extraordinary. The Senate appointed Quintus Fabius Maximus dictator. Fabius adopted his namesake strategy: shadow Hannibal, refuse pitched battle, and let logistics work. Romans, expecting their generals to fight, derided him as Cunctator or "the Delayer". The Sibylline Books were consulted, a ver sacrum vowed, temple construction promised, and silver coins struck including this quadrigatus, all in an attempt to placate the gods.