In Persia and Babylon, the festival was called Sacaea. This appears to be the original tradition in which masters and slaves traded roles and in which one of the slaves was appointed head of the household.
As played out in ancient Babylon, in proper season the king would repair to the temple dedicated to Marduk, be stripped of his insignia by the chief priest and swear that in the past year he had done nothing wrong. The chief priest then would speak for Marduk and re-invest the king with his kingdom. We can see how the priestly class simultaneously protected its power and provided an explanation for terrifying, unexplainable natural events.
