Gaius Calpurnius Piso, consul in 67 BC, an optimate and confirmed opponent of Pompey. He resisted the lex Gabinia, governed Narbonese Gaul as proconsul, and was successfully defended by Cicero on a charge de repetundis in 63 BC. He recurs in the Philippics and Pro Caecina as a senior figure of Cicero's consular circle.