Publius Helvius Pertinax (c.181-213): son of the Roman emperor with the same name, consul in 213, killed by the emperor Caracalla.
The year of Publius' birth is unknown, but we can make an educated guess. In 193, his father Pertinax was murdered by rebellious soldiers of the imperial guard. The deed was immediately regretted and the throne was offered to Pertinax' father-in-law Titus Flavius Sulpicianus. This means that Publius, who should have succeeded his father, was not yet at an age to rule. As he was consul in 213, an office for which one had to be 32 years old, it is likely that he was born in 181, and ten or eleven when his father was killed.
His father's rule started after the assassination of Commodus in the night of 31 December 192 / 1 January 193. Although the Senate offered the boy the title of caesar, "intended successor", his father declined this, declaring that Publius should be made caesar "when he has earned it". (This also suggests that he was a mere boy when his father became Rome's highest official.) On several coins, however, the title "caesar" is used for the boy. The explanation is probably that the provincial officials responsible for the minting of coins were not yet aware of the constitutional niceties.
His father was killed on 28 March 193, after a reign of eighty-six days, and was succeeded by Didius Julianus, who was in turn killed by adherents of Septimius Severus in June 193. The young man was appointed as priest (flamen) of the deified Pertinax. He could now style himself "son of god" - something he of course did not, because that would have been an insult to the ruling dynasty of Septimius Severus.
In 213, Publius Helvius Pertinax was made consul suffectus, i.e. one of the consuls after the year's first pair of consuls (in January). If Publius had had a normal senatorial career (cursus honorum), he must have been governor in 212, praetor in 211, aedile in 208, quaestor in 206, and military tribune in 201.
The collection of imperial biographies known as Historia Augusta informs us that as a consul, he once made a joke that was not appreciated by the emperor Caracalla (211-217).note[Historia Augusta, "Caracalla" 10.6.] The ruler had claimed several honorific titles (such as Germanicus, Parthicus, and Arabicus) because he had defeated the Germanic tribes, the Parthians, and the Arabs of Edessa. Now Publius said that the emperor ought to add Geticus, which might mean that Caracalla had defeated the Getae - but was also a reminder that the emperor had killed his brother Geta (in December 211).
Needless to say, the emperor was not amused. Publius Helvius Pertinax, although a consul, was executed immediately.