'First Our Neighbours, Then the World' examines the growth of the Roman state and its army from the early battle of Veii, in which the Etruscan kings were routed, to the Celtic sack of Rome and the subsequent reorganisation of the army that went on to wrest control of the Mediterranean from Carthage in the Punic Wars. Late Republican power struggles culminating in the dictatorship of Julius Caesar resulted in the formation of the professional army that forged the Empire.
'Roman Versus Roman' chronicles the moment when the military turned against its own leaders. The Civil Wars and the reign of Augustus as first Emperor of Rome are charted.
'Roman Siege Warfare' details the mass mobilization of its troops that allowed Rome to conquer all before it. Episode opens with some fascinating demonstrations of siege equipment, including devastatingly deadly bolt-firing catapults and stone-throwing ballistae. The famous sieges of Jerusalem (in 66 AD) and Masada in Judea are covered, then the programme describes the life of a soldier in a typical Roman fort, such as Vindolanda on Hadrian's wall, illustrating the change in the army from an offensive to a defensive force.
'Barbarians at the Gate' documents that by the second century AD, the people they had vanquished had developed territorial ambitions of their own. In this final episode the steady decline of the Empire is sketched, the military reforms of Diocletian and Constantine are touched upon, as is the process of barbarisation of the army, before the collapse of the Western Empire in the fifth century.