One of the themes of the festival was the temporary subversion of order. Masters and servants reversed roles. The king dressed in white would change place with ordinary people. A mock king was crowned and masquerades spilled into the streets. As the old year died, rules of ordinary living were relaxed. This tradition persisted till the Sassanian rule and is mentioned by Birouni, the eminent scientist and traveler, and others in their recordings of pre-Islamic rituals and festivals.