The city of Rome and the lands of Italia are in the hands of a usurper. To the west, the Gallic provinces have named themselves ‘Gallic Rome’ and pursue independence, supported by the Roman governors in Hispania and Britannia. To the east, the forces of the Palmyrene queen, Zenobia, converge on Egypt, driven by her raw ambition to achieve imperial status for both her and her son. After a period of civil war lasting more than twenty years, the Roman Empire has split apart.