Numerius Fabius Vibulanus

In 421 BC Fabius was elected as consul together with Titus Quinctius Capitolinus Barbatus. As consuls Fabius fought and defeated the Aequi and was awarded an ovatio (minor triumph) for his victories. The year also saw the consuls overseeing the institution of a new law increasing the number of Quaestors from two to four.[3][4][5][6]

In 415 BC, Fabius was elected as one of the Consular tribunes, his colleagues were Publius Cornelius Cossus, Gaius Valerius Potitus Volusus and Quintus Quinctius Cincinnatus. The actions of the consulars of this year is little known, but there was a proposal by the plebeian tribune Lucius Decius to colonize Bolae which was vetoed.[7][8][9][10]

Fabius was elected for a second time as consular tribune in 407 BC. He shared the office with his former colleague Valerius and two others, Lucius Furius Medullinus and Gaius Servilius Ahala. All members of the consular college this year had previously held the imperium. Even though the college consisted of experienced and decorated military leaders they lost against the Volscians which resulting in the loss of the city of Verrugo.[11][12][13][14]

Fabius could have been one of the unknown censors who completed the lustrum in between 417 and 404 BC as suggested by the classicist Jaakko Suolahti. Suolahti, drawing from the fact that the census described in 403 is numbered lustrum XVI and counting from lustrum X which was held in 459 BC only gives us four pairs of censors (in 443, 435, 430 and 418 BC), thus a missing lustrum XV. Additionally drawing upon a gap in the Fasti Capitolini from 414 to 410 BC the censorship can likely be placed within this timeframe, with Suolahti leaning towards the year 410 BC. Suolahti's main suggestions for these unknown censors are Spurius Nautius Rutilus and Manius Aemilius Mamercinus but adds Fabius as one of the viable options. While Suolahti argues for the existence of these unknown censors and lustrum XV, these possible candidates should be noted, and is noted by the author himself, are simply educated guesses based on the suitability of the candidates to the office and are in the authors words "mere suppositions".[15]

There exist some confusion in regards to the praenomen of Fabius. The ancient historian Livy has him named Gnaeus while the Fasti Capitolini has his name as Numerius. Gnaeus is not otherwise attested within the Fabii while Numerius (prior to this Fabius unattested within the Fabii) would become increasingly popular within the gens, especially in the subbranches of the Pictores and Buteones. There is little consensus in regards to the name, but the classicist Degrassi considers Gnaeus the likeliest alternative while Broughton provides both Gnaeus and Numerius as alternatives.[16][17][18]

The confusion intensifies in regards to the ancient records of Fabius in 415 and 407 BC where he is given four different praenomens; Gaius, Marcus, Numerius and Gnaeus. Livy has him as Marcus in 415 and as Gnaeus in 407, the Fasti is damaged in 415, giving no praenomen while calling him Numerius II in 407 BC and finally the historian Diodorus names him as Gaius in both 415 and 407 BC. Here Broughton prefers Numerius and considers him the same individual as the consul in 421 BC.[19] While there is no clear consensus of the praenomen of Fabius the majority of both ancient and modern scholars considers the consul of 421 and the consular tribune of 415 and 407 BC to be the same individual.

• Fabia gens – Ancient Roman family