Princeps senatus

The Princeps senatus (plural principes senatus) was the leader of the Roman senate. Although officially out of the cursus honorum and owning no imperium, this office brought enormous prestige to the magistrate holding it.

The princeps senatus was not, like most Roman offices, a lifetime job. He was chosen by every new pair of censors (that is, every five years). Censors could, however, confirm a princeps senatus for a period of another five years. He was selected from patrician senators with consular rank, usually former censors. The successful candidate had to be a patrician with an impeccable political record, respected by his fellow senators.

The office tasks include:

Declaring opening and closure of the senate sessions
Deciding the agenda
Deciding where the session should take place
Imposing order and other rules of the session
Meeting, in the name of the senate, with embassies of foreign countries
Writing, in the name of the senate, letters and dispatches

After the fall of the Roman Republic, the princeps senatus was the Emperor.

Incomplete List of Principes Senatus

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214 BC – Marcus Fabius Buteo
209 BC – Quintus Fabius Maximus Verrucosus
199 BC – Publius Cornelius Scipio Africanus Major
184 BC – Lucius Valerius Flaccus
179 BC – Mamercus Aemilius Lepidus
147 BC – Publius Cornelius Scipio Nasica
136 BC – Appius Claudius Pulcher
131 BC – Lucius Cornelius Lentulus Lupus
125 BC – Publius Cornelius Lentulus
115 BC – Marcus Aemilius Scaurus
86 BC - Lucius Valerius Flaccus
…