This is a dual biography of the emperors Marcus Antonius Gordianus ('Gordian III', reigned 238-244) and Marcus Julius Philippus Augustus ('Philip the Arab', reigned 244-249), focusing mainly on the political and military events during this crucial stage of the 'Third Century Crisis'. The tumultuous 'Year of the Six Emperors' saw Gordian raised to the purple at just thirteen years of age, becoming the youngest emperor in the Empire's history at a time when the borders were threatened by the powerful Sassanid Persians and the Goths, among others. Gordian died on a campaign against the Persians, either in battle or possibly murdered by his own men.

Philip, succeeded Gordian, made peace with Shapur I and returned to Italy. His reign encompassed the spectacular celebration of Rome's millennium in 248 but the wars in the Balkans and East together with crippling taxation led to mutinies and rebellions. Philip and his brother had until then fought successfully against the Persians and others but this did not save Philip, who was killed by a usurper's forces at the Battle of Verona in 249. He had been Rome's first Christian emperor and the author considers why it was fifty years before she had another.