- For the spider genus, see Cethegus (spider).
Cethegus is the cognomen of the patrician family of the ancient Roman Cornelian gens. Like the younger Cato its members kept up the old Roman fashion of dispensing with the tunic and leaving the arms bare. The following individuals are of some importance:
- Marcus Cornelius Cethegus, curule aedile, 213 BC. In 211 BC, as praetor, he had charge of Apulia; later, he was sent to Sicily, where he proved a successful administrator. In 209 BC he was censor, and in 204 BC consul. In 203 BC he was proconsul in Upper Italy, where, in conjunction with the praetor Publius Quintilius Varus, he gained a hard-won victory over Mago Barca, Hannibal's brother, in Insubrian territory, and obliged him to leave Italy. He died in 196 BC. He had a great reputation as an orator, and is characterized by Ennius as the quintessence of persuasiveness (suadae medulla). Horace calls him an authority on the use of Latin words.
- Gaius Cornelius Cethegus became proconsul in Spain in 200 BC and was elected aedile in absentia. In this office he arranged magnificent plays. During his consulate in 197 BC he fought successfully in Gallia Cisalpina against the Insubrians and Cenomanes and received a triumph. He was elected censor in 194 BC. Along with Scipio Africanus and Marcus Minucius Rufus in 193 BC, he went as a commissioner to mediate an end to the war between Masinissa and Carthage.
- Publius Cornelius Cethegus, consul in 181 BC
- Publius Cornelius Cethegus, senator during the 1st century BC
- Gaius Cornelius Cethegus, the boldest and most dangerous of Catiline's associates. Like many other youthful profligates, he joined the conspiracy in the hope of getting his debts cancelled. When Catiline left Rome in 63 BC, after Cicero's first speech, Cethegus remained behind as leader of the conspirators with Lentulus Sura. He himself undertook to murder Cicero and other prominent men, but was hampered by the dilatoriness of Sura, whose age and rank entitled him to the chief consideration. The discovery of arms in Cethegus's house, and of the letter which he had given to the ambassadors of the Allobroges, who had been invited to cooperate, led to his arrest. He was condemned to death, and executed, with Sura and others, on the night of 5 December.
- Servius Cornelius Cethegus, consul of AD 24.