There is no doubt that Rome developed one of the most efficient and successful military systems of the ancient world. The famous legions conquered from the Atlantic to the Euphrates, from the Scottish Highlands to the sands of the Sahara, defeating all manner of enemies. Although their victories were many, they were never invincible and did suffer significant defeats. Ian Hughes looks at thirteen such occasions, narrating the course of the fighting (in as much detail as the sources allow), describing the forces involved, the strategy and tactics employed and the reasons for the Roman defeat. The chosen battles span the centuries, from the disastrous battle against invading Celts at the Allia River in (387 or 386 BC) to the naval defeat by the Vandals off Cap Bon in AD 468\. They are selected either for the magnitude of the tactical defeat or the political and strategic significance of the outcome. Apart from the inherent interest in the individual battles, this study offers a survey of the development of the Roman forces evolving to survive.