Publius Postumius Tubertus, the son of Quintus, was the first of the patrician gens Postumia to obtain the consulship, which he held in 505 BC, and again in 503. Ten years later, he was one of the envoys sent by the Roman Senate to negotiate with the plebeians during the first secessio plebis. The outcome of those negotiations reunited the Roman people, and established the tribunes of the plebs, one of the most important institutions of the Roman Republic.[1]
Postumius' first consulship came in 505 BC, the fifth year of the Republic. Together with his colleague, Marcus Valerius Volusus, he fought against the Sabines, whom they defeated decisively near Tibur, obtaining a triumph.[2][3][4][5][6]
Postumius was consul for the second time in 503 BC. Livy records that he fought and defeated the Aurunci, and captured the town of Pometia, obtaining a second triumph.[2] Other authorities state that he fought against the Sabines again, at first with little success, but that he was eventually victorious, and was awarded an ovation, or lesser triumph, which he celebrated on 3 April 503 BC.[7][5] This was the first occasion that this honour was bestowed upon a magistrate of the Republic.[8][9] Additionally, according to Jerome, Postumius and his colleague, Agrippa Menenius Lanatus, held a census during their term of office.[10][11]
In 493 BC, Postumius and Menenius were among the ten ambassadors sent by the senate to treat with the plebs gathered on the Mons Sacer during the first secession. Led by Menenius, the envoys successfully negotiated an agreement under which the patricians would forgive some of the debt owed by the plebeians; the terms of the agreement also established the office of the tribuni plebis, or "tribunes of the people", who received the power to veto acts of the magistrates and the senate.[12][13][14]
In consequence of his deeds and reputation, Postumius and his descendants were accorded the privilege of being buried within the city walls.[15]