Herennius Senecio was among the Stoic

STOIC

STOIC was a variant of Forth.It started out at the MIT and Harvard Biomedical Engineering Centre in Boston, and was written in the mid 1970s by Jonathan Sachs...

 opposition to the emperor Domitian

Domitian

Domitian was Roman Emperor from 81 to 96. Domitian was the third and last emperor of the Flavian dynasty.Domitian's youth and early career were largely spent in the shadow of his brother Titus, who gained military renown during the First Jewish-Roman War...

, under whose rule he was executed. He was from Baetica in Roman Spain. He was the author of a laudatory biography of the Stoic martyr Helvidius Priscus

Helvidius Priscus

Helvidius Priscus, Stoic philosopher and statesman, lived during the reigns of Nero, Galba, Otho, Vitellius and Vespasian.Like his father-in-law, Thrasea Paetus, he was distinguished for his ardent and courageous republicanism. Although he repeatedly offended his rulers, he held several high offices...

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In 93 AD, Herennius and Pliny

Pliny the Younger

Gaius Plinius Caecilius Secundus, born Gaius Caecilius or Gaius Caecilius Cilo , better known as Pliny the Younger, was a lawyer, author, and magistrate of Ancient Rome. Pliny's uncle, Pliny the Elder, helped raise and educate him...

 successfully prosecuted a case against Baebius Massa for improprieties during his administration in Baetica. Baebius's property was confiscated in order to make reparations to the provincials. Baebius retaliated by bringing a charge of treason (maiestas) against Herennius, accusing him of impietas, but dropped the case when Pliny threatened a counter suit.

Mettius Carus, however, managed to convict Herennius. Although the details of the case are unclear, several factors rendered Herennius vulnerable. Because he had declined to run for any office after he was quaestor

Quaestor

A Quaestor was a type of public official in the "Cursus honorum" system who supervised financial affairs. In the Roman Republic a quaestor was an elected official whereas, with the autocratic government of the Roman Empire, quaestors were simply appointed....

, he might be accused of desertion of public duty (secessio). He was connected by friendship and possibly blood to the emperor's enemies. In his biography of Helvidius, Herennius was praising an unrelenting critic of Domitian's father. Helvidius's widow Fannia

Fannia

Fannia is notable as the granddaughter of the well-known Arria Major.Fannia is recorded in the writings of Pliny the Younger as a woman of fortitude and respectability.As with her grandmother, Fannia is described as a political rebel in her own right...

, the daughter of Thrasea Paetus, had given Herennius her late husband's notebooks (commentarii); for this she was also prosecuted by Carus and condemned to exile. Another member of this circle who fell victim to Domitian was Arulenus Rusticus

Arulenus Rusticus

Quintus Junius Arulenus Rusticus, , is more usually called Arulenus Rusticus, but sometimes also Junius Rusticus. He was a friend and follower of Thrasea Paetus, and, like the latter, an ardent admirer of Stoic philosophy...

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