When Vardanes II of Parthia rebelled against his father Vologases I in 55 AD, Vologases withdrew his forces from Armenia. Rome quickly attempted to fill the political vacuum left behind. In the Roman–Parthian War of 58–63 AD, the commander Gnaeus Domitius Corbulo achieved some military successes against the Parthians while installing Tigranes VI of Armenia as a Roman client. However, Corbulo's successor Lucius Caesennius Paetus was soundly defeated by Parthian forces and fled Armenia. Following a peace treaty, Tiridates I traveled to Naples and Rome in 63 AD. At both sites the Roman emperor Nero ("r". 54–68 AD) ceremoniously crowned him king of Armenia by placing the royal diadem on his head.