The object of this work is to trace the growth of the Roman constitution, and to explain its working during the two phases of its maturity, the developed Republic and the Principate. The title selected perhaps expresses more succinctly than any other could do the nature of the plan which I wished to undertake. My desire was to touch, however briefly, on all the important aspects of public life, central, municipal, and provincial; and, thus, to exhibit the political genius of the Roman in connexion with all the chief problems of administration which it attempted to solve. This design, like many other comprehensive plans which have to be adapted to the limits of a single volume, was necessarily subjected to modifications in detail; and, since one of these modifications has affected the whole scope of the book, it requires some mention in a preface.
I had intended to carry the treatment of my subject beyond the confines of the Principate, and to describe the political organisation of the later Empire as elaborated by Diocletian and his successors. I found, however, that a discussion of this period would cause my work to exceed the reasonable limits which can be conceded to a handbook, and I was forced to abandon the enterprise much against my will. I was somewhat comforted in this surrender by the suggestion that the constitution of the later Empire was perhaps not strictly "Roman." This is a verdict with which I agree in part. The organisation which had Constantinople as its centre was certainly the organisation of an Empire which was permeated with the social
