Senate of the Roman Empire

The Senate of the Roman Empire was a political institution in the ancient Roman Empire. After the fall of the Roman Republic, the constitutional balance of power shifted from the "Roman Senate" to the "Roman Emperor." Beginning with the first emperor, Augustus, the Emperor and the Senate were technically two co-equal branches of government. In practice, however the actual authority of the imperial Senate was negligible, as the Emperor held the true power of the state. As such, membership in the Senate became sought after by individuals seeking prestige and social standing, rather than actual authority. During the reigns of the first Emperors, legislative, judicial, and electoral powers were all transferred from the "Roman assemblies" to the Senate. However, since the control that the Emperor held over the senate was absolute, the Senate acted as a vehicle through which the Emperor exercised his autocratic powers.

The first emperor, Augustus, inherited a Senate whose membership had been increased to 900 senators by his predecessor, the "Roman Dictator" Julius Caesar. Augustus sought to reduce the size of the Senate, and did so through three revisions to the list of senators. By the time that these revisions had been completed, the Senate had been reduced to 600 members, and after this point, the size of the Senate was never again drastically altered. To reduce the size of the senate, Augustus expelled senators who were of low birth, and then he reformed the rules which specified how an individual could become a senator. Under Augustus' reforms, a senator had to be a citizen of free birth, and have property worth at least 1,000,000 sesterces.

Under the Empire, as was the case during the late Republic, one could become a senator by being elected "Quaestor" (a magistrate with financial duties). Under the Empire, however, one could only stand for election to the Quaestorship if one was of senatorial rank, and to be of senatorial rank, one had to be the son of a senator. If an individual was not of senatorial rank, there were two ways for that individual to become a senator. Under the first method, the Emperor granted that individual the authority to stand for election to the Quaestorship, while under the second method, the Emperor appointed that individual to the senate by issuing a decree (the adlectio).

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