Senatus

Senatus is the Latin word for the Senate, the primary deliberative and governing body of ancient Rome. Its members were called senatores, traditionally drawn from Rome’s elder and aristocratic families, and the term is used in Latin texts to describe the institution as a whole. The Senate’s composition expanded over time to include some wealthier plebeians, but it remained an elite body throughout most of Roman history.

Origins of the senatorial institution lie in Rome’s early monarchy and were formalized during the Republic after 509 BCE. The Senate served as the chief advisory council to the magistrates, guiding policy on military, foreign, financial, and religious matters. It met in the Curia, and membership was for life, with the body generally numbering from 300 to about 600 members at various periods. The Senate’s authority rested in prestige, tradition, and control over public finances and provincial appointments.

During the Republic, the Senate could issue decrees known as senatus consulta, which, while technically advisory, framed policy and could strongly steer political decisions. Its influence waxed and waned with political turmoil, enriching its role in approving treaties, funding, and major state projects. Extraordinary measures, such as the senatus consultum ultimum, were also issued in emergencies to authorize exceptional actions.

Under the Empire, imperial authority gradually centralized power, and the Senate became largely subordinate, though it continued to function as a court of governance, a formal municipal body in Rome, and a prestige-filled symbol of continuity. The institution persisted in name and ceremonial authority long after real political power had shifted to the emperors.

The Senate's legacy influences later political thought, and the Latin term remains a common reference in discussions of Roman governance. The phrase Senatus Populusque Romanus (SPQR) embodies the enduring association between the Senate and the Roman state.