The historian Dio Cassius (2nd to 3rd century CE) tells how the name of Mithras was spoken during the state visit to Rome of Tiridates I of Armenia, during the reign of Nero. (Tiridates was the son of Vonones II of Parthia, and his coronation by Nero in 66 CE confirmed the end of a war between Parthia and Rome.) Dio Cassius writes that Tiridates, as he was about to receive his crown, told the Roman emperor that he revered him "as Mithras". Roger Beck thinks it possible that this episode contributed to the emergence of Mithraism as a popular religion in Rome.