It was restored to its official status after the reconquest of Italy by Justinian I but the Western Senate ultimately disappeared after 603, the date of its last recorded public act.
[5] Over time, the patres came to recognize the need for a single leader, and so they elected a king (rex),[5] and vested in him their sovereign power.
[9] Rome's seventh and final king, Lucius Tarquinius Superbus, executed many of the leading men in the senate, and did not replace them, thereby diminishing their number.
The Senate held the fiscal responsibilities of the Roman Republic's treasury holding a regulatory power over incoming and outgoing transactions.
[16] Senators were entitled to wear a toga with a broad purple stripe, maroon shoes, and an iron (later gold) ring.
If there was no veto and no obvious majority, and the matter was of a significant nature, there was usually a physical division of the house,[20] with senators voting by taking a place on either side of the chamber.
They could not own a ship that was large enough to participate in foreign commerce,[20] they could not leave Italy without permission from the rest of the senate and they were not paid a salary.
Though retaining its legal position as under the republic, in practice the actual authority of the imperial senate was negligible, and the emperor held the true power in the state.
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), but only if one were already of senatorial rank.
[26] In addition to quaestors, elected officials holding a range of senior positions were routinely granted senatorial rank by virtue of the offices that they held.
[31] While the Roman assemblies continued to meet after the founding of the empire, their powers were all transferred to the senate, and so senatorial decrees (senatus consulta) acquired the full force of law.
In the final years of the western empire, the senate would sometimes try to appoint their own emperor, such as in the case of Eugenius, who was later defeated by forces loyal to Theodosius I.
The senate remained the last stronghold of the traditional Roman religion in the face of the spreading Christianity, and several times attempted to facilitate the return of the Altar of Victory (first removed by Constantius II) to the senatorial curia.
"And Elagabalus was the only one of all the emperors under whom a woman attended the senate like a man, just as though she belonged to the senatorial order" (David Magie's translation).
According to the same work, Elagabalus also established a women's senate called the senaculum, which enacted rules to be applied to matrons regarding clothing, chariot riding, the wearing of jewelry, etc.
After the fall of the Western Roman Empire, the senate continued to function under the Germanic chieftain Odoacer, and then under Ostrogothic rule.
It is known that the senate successfully installed Laurentius as pope in 498, despite the fact that both King Theodoric and Emperor Anastasius supported the other candidate, Symmachus.
[33] The peaceful coexistence of senatorial and barbarian rule continued until the Ostrogothic leader Theodahad found himself at war with Emperor Justinian I and took the senators as hostages.
Many senators had been killed and many of those who had fled to the east chose to remain there, thanks to favorable legislation passed by Emperor Justinian, who, however, abolished virtually all senatorial offices in Italy.
The importance of the Roman senate thus declined rapidly,[36][37] and it likely ceased to function as an institution with any real legislative power shortly after this time.
Records that in both 578 and 580, the politically-impotent senate of Rome sent envoys to Constantinople along with pleas for help against the Lombards, who had invaded Italy ten years earlier.
Later, in 593, Pope Gregory I would give a sermon in which he bemoaned the almost complete disappearance of the senatorial order and the decline of the prestigious institution,[39][40] suggesting that by this date, the senate had officially ceased to function as a body.
[42] In 630, any remnants of the senate were swept away when the Curia Julia was converted into a church (Sant'Adriano al Foro) by Pope Honorius I.
[citation needed] The Commune came under constant pressure from the papacy and the Holy Roman Emperor during the second half of the twelfth century.
Designated in Greek as synkletos, or assembly, the Senate of Constantinople was made up of all current or former holders of senior ranks and official positions, plus their descendants.
At its height during the 6th and 7th centuries, the Senate represented the collective wealth and power of the Empire, on occasion nominating and dominating individual emperors.
[53] In the second half of the 10th century a new office, proedros (Greek: πρόεδρος), was created as head of the senate by Emperor Nicephorus Phocas.
Up to the mid-11th century, only eunuchs could become proedros, but later this restriction was lifted and several proedri could be appointed, of which the senior proedrus, or protoproedrus (Greek: πρωτοπρόεδρος), served as the head of the senate.
The Senate in Constantinople existed until at least the beginning of the 13th century, its last known act being the election of Nicholas Kanabos as emperor in 1204 during the Fourth Crusade.