The only member of the gens to attain any prominence in the Roman state was Sextus Pompilius, who was tribune of the plebs in 420 BC; however, persons by this name are occasionally found throughout the history of the Republic.
By all accounts, Pompilius was a Sabine, renowned for his wisdom, and living at the town of Cures at the time of the death of Romulus.
The tradition reported by the Roman historians is that the selection of a foreigner over one of the leading Roman citizens was urged by Rome's considerable Sabine populace, which had not only enjoyed equal status with the Latin inhabitants of Rome, but had their own king, Titus Tatius, ruling alongside Romulus for part of his reign.
[2][3] A common practice in the later Republic was for gentes to claim descent from figures associated with the founding of Rome, the companions of Aeneas, or individuals who lived in the time of the kings.
The Pomponii claimed descent from this son, and both their nomen and that of Pompeius are occasionally confounded with Pompilius in the ancient writers.