Livia Orestilla, or Cornelia Orestilla was a Roman Empress as the second wife of the Emperor Caligula in AD 37 or 38. She was originally married to Gaius Calpurnius Piso (in particular the one involved in a conspiracy to overthrow the emperor Nero in AD 65), who was persuaded or forced to annul the marriage so that Caligula could marry her. According to both Dio and Suetonius, this occurred during Piso and Orestilla's wedding celebrations. Suetonius claims that Caligula issued a proclamation the next day that he had acquired a new wife in the tradition of Romulus and Augustus, who had both stolen wives from other men. On the next day Caligula divorced with Orestilla; however, he also prohibited her from getting into a relationship with Piso again. In two years both Orestilla and Piso were banished for adultery to a distant island.