Publius Pasidienus Firmus

Publius Pasidienus Firmus was a Roman senator, who was active during the reign of Nero. He was suffect consul in the second quarter of 65 as the colleague of Aulus Licinius Nerva Silianus, replacing Marcus Julius Vestinus Atticus whom Nero forced to commit suicide. Firmus is known entirely from inscriptions.

Pasidienus is a rare gentilicium. Bernard Remy believes it is Etruscan in origin. However, noting that the suffix -enus was typical of names from Picenum and the vicinity, other authorities believe that the Pasidieni were of Picentine or Umbrian descent.

Based on a fragmentary inscription, Attilio Degrassi identified Firmus with the ordinary consul for the year, Nerva Silianus, arguing that Nerva Silianus had a polyonymous name. Some authorities were uncomfortable with this identification, since it presumed Firmus had been adopted by a member of the patrician Licinii Nervae, which would lead to a number of problems. The discovery of a military diploma dated to 18 June of the consulship of Nerva Silianus and Pasidienus Firmus decisively proved they were two different men.

It is clear that he is related to Lucius Pasidienus Firmus, suffect consul in 75. If the younger Firmus were his son, the unusually brief period between their consulates would help confirm the theory he came to the consulate late in life. However, it is equally possible the younger Firmus could be a nephew or a cousin.