Sulpicius was a member of the gens Sulpicia, a prominent patrician family which had attained the consular dignity a great number of times following the foundation of the republic.
This term as consular tribune is not certain however, as while he is mentioned as holding the position by the Fasti Capitolini and Diodorus Siculus, the historian Livy only records six men in that year's college, with Sulpicius being left out.
Nothing is known of his term as censor other than that his colleague Postumius may died midway through the lustrum due to a pestilence, forcing Sulpicius to resign in accordance to Roman religious tradition.
In this year the pestilence which killed Sulpicius' previous colleague Postumius raged on, and in response the consuls prepared a ritual feast to the gods in order to appease them.
However, when this rite failed to achieve its intended result, the consuls tried a more unorthodox tactic, and invited Etruscan musicians and dancers to put on theatrical performances.
Shortly afterwards, Appius Claudius Crassus, the dictator appointed by the senate in response to Genucius' death, arrived with a new army and commended the bravery of Sulpicius and his men.
[6][7] In 358 BC, rumours spread of a Gallic invasion, and since both consuls were occupied with other campaigns, Sulpicius was appointed dictator by the senate to combat this threat.
As a result, Sulpicius resolved to take the enemy by surprise, and concocted a scheme in which to do so, involving sending muleteers and cavalrymen on a nearby mountain to lie in wait until he gave them a signal to charge.
In the morning, Sulpicius then lined his troops on the foot of the mountain, so that the Gauls were required to fight facing the mount, thus setting the stage for a flanking attack.
More pressingly however, class tensions were inflamed this year, with the plebeians feeling disenfranchised as a result of the patrician order having elected two of their own in violation of the Lex Licinia Sextia.
Thus Sulpicius marched to Tarquinii and ravaged their territory, but also found that not only had the Roman salt works been raided, but the loot had been sent in the direction of Caere, another Etruscan city.