Book excerpt: In the years between 31 BC and AD 500 the Romans carved out a mighty empire stretching from Britain to the deserts of North Africa. The men who spearheaded this expansion were the centurions, the tough, professional warriors who led from the front, exerted savage discipline and provided a role model for the legionaries under their command. This book, the second volume of a two-part study, reveals the appearance, weaponry, role and impact of these legendary soldiers during the five centuries that saw the Roman Empire reach its greatest geographical extent under Trajan and Hadrian, only to experience a long decline in the West in the face of sustained pressure from its 'barbarian' neighbours. Featuring spectacular full-colour artwork, written by an authority on the army of the Caesars and informed by a wide range of sculptural, written and pictorial evidence from right across the Roman world, this book overturns established wisdom and sheds new light on Rome's most famous soldiers during the best-known era in its history.