The various public offices here referred to will be discussed in the later chapters as each office first comes into existence in Roman history. It remains at this time to speak of the organization, powers, and authority of the Roman Senate, particularly as to its control over the work of the popular assemblies.
The extent of the power of the Senate over legislation varied greatly in different periods of Roman history, and these differences were caused more by the existing political conditions, and by the relative strength of the aristocratic and popular parties in Rome, than by any express changes by legislation.
At the very outset of Roman history we see the Senate existing as an aristocratic body, embodying in itself both the oligarchical principles upon which the Roman government was based, and also the patriarchal basis upon which the Roman family organization and later the organization of the Roman state itself had been built.
Originally, each of the three Roman tribes was divided into ten gentes, each gens into ten curiæ, and each curia, besides constituting one of the units in the comitia curiata, furnished one member of the Roman Senate. The Senate continued after the organization by curiæ had become obsolete. Membership in the Senate was at all periods for life, but did not descend from father to son. Vacancies in the Senate were filled by appointment, these appointments being made first by the kings, later by the consuls, and finally by the censors. As the censors were chosen only once in five years, vacancies in the Senate were filled only at such intervals. The aristocratic party in Rome, by keeping control of the office of censor, was able to perpetuate their majority in the Senate. In filling such vacancies, preference was given to those who had held some of the higher offices during the preceding five-year-period. Many members of the Senate had held the office of consul; many more hoped to hold it in the future. All members of the Senate, with few exceptions, had held some civic office, and were men of property and of mature age.
All the dignity of Rome and of the Roman government centered in the Roman Senate. The minister of Pyrrhus described this body as "an assembly of kings," and it might well have aroused the surprise and admiration of a foreign ambassador, as nowhere else in the world at that time was it possible to find such an assembly, either from the standpoint of the character of the body itself or of the qualifications of its members.