E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
King of Misrule.
Sometimes called LORD, and sometimes ABBOT, etc. At Oxford and Cambridge one of the Masters of Arts superintended both the Christmas and Candlemas sports, for which he was allowed a fee of 40s. These diversions continued till the Reformation. Polydore Vergil says of the feast of Misrule that it was derived from the Roman Saturnalia, held in December for five days (17th to 22nd). The Feast of Misrule lasted twelve days.
If we compare our Bacchanalian Christmases and New Year-tides with these Saturnalia and Feasts of Janus, we shall finde such near affinitye between them both in regard of time and in their manner of solemnising that wee must needs conclude the one to be the very ape or issue of the other.Prynne: Histrio-Mastix.