The Olympic Games reached the height of their success in the 6th and 5th centuries BC, but then gradually declined in importance as the Romans gained power and influence in Greece. While there is no scholarly consensus as to when the Games officially ended, the most commonly held date is 393 AD, when the emperor Theodosius I decreed that all pagan cults and practices be eliminated. Another date commonly cited is 426 AD, when his successor, Theodosius II, ordered the destruction of all Greek temples.