Abstract

It is difficult to provide a definition of the concept of Roman empire essentially because of the lack of an adequate theoretical reflection in the ancient sources and the reference to a "constitutional charter". The ambiguous origin of the Augustan "res publica restituta" brings forth the problem of the nature of the "princeps"' powers and their legitimacy, in relation to the traditional republican institutions, conceived to prevent the introduction of an oriental type of regality. Within the historical development of the principate, from Adrian to the Severi, the drive towards ideological production went hand in hand with an equally impellent need to develop organisational instruments to govern spaces and peoples in a delicate balance between administrative centralisation and local autonomy, which allowed a solid process of acculturation, in accordance with the ecumenical vocation of the empire.