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

The princeps senatus was not, like the most of 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 must be a patrician with 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 an other rules of the session
  • Meet, 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