The rise of Rome depended on fearsome military prowess, backed up by an unprecedented willingness to accept conquered enemies into society as Romans. This combination of 'the sword and the open hand' built one of the world's greatest empires.Yet under the emperors 'the Roman army' was far from the monolithic military machine that is generally assumed. The armies (plural) were multi-ethnic, often based far from Italy, and they established a military identity that quickly diverged from that of the civil centre. The soldiers could form well-disciplined fighting units, bearing murderously efficient weapons, but they were also habitually unruly, and could be as dangerous to their own citizens, to their emperors, or to each other, as to their enemies. Simon James brings thirty years' study of Roman history and ancient military technology, and a vivid storytelling style, to this groundbreaking new account of how warriors and weapons both forged the Roman empire and sowed the seeds of its destruction.