Trajan (AD 98-117) is one of the very few Roman emperors who has always been seen in a good light. Popular during his lifetime, by the fourth century he had become the litmus test of imperial excellence. In the Middle Ages he was placed by Dante in the sixth sphere of Heaven among the Just and Temperate Rulers, and for Gibbon, Trajan's principate ushered in the Golden Age of the Roman Empire.

In this the first comprehensive biography in English, Julian Bennett tests the substance of the emperor's glorious reputation. No ancient biography of Trajan survives and the period as a whole is singularly ill-served by the extant literary evidence. A thorough examination of the contemporary archaeological and epigraphic evidence supplements this inadequate written record and allows Dr Bennett to cover every major aspect of Trajan's reign.

Dr Bennett's central conclusion is that Trajan's reign was indeed the apogee of the principate established by Augustus and his successors. It saw the birth of the 'imperiate' - the full realization of the imperial system. Moreover, the emperor himself is seen as the pivotal character in this development. Trajan's contemporary reputation as Optimus Princeps seems to have been richly deserved.