This essay takes issue with Charles Halperin’s assertion, in his book on Ivan the Terrible, that the state terror imposed by the tsar in the period of the oprichnina bore no relation to the concept of carnival employed by Mikhail Bakhtin. The reviewer argues that, on the contrary, Ivan’s behaviour was heavily influenced by aspects of the “comic world” of early Rus’ identified by D.S. Likhachev and A.M. Panchenko as the Muscovite equivalent of the Western European “carnivalesque”. She examines the deposition and ritual humiliation of Metropolitan Filipp of Moscow and Archbishops Pimen and Leonid of Novgorod, and the murder of the boyar I.P. Fedorov-Cheliadnin, and shows that these had much in common with forms of popular culture. Similarly, the oprichniki themselves in some respects resembled mummers, and their monastery at Aleksandrovskaia Sloboda was carnivalesque. The oprichnina terror displayed some of the gruesome rituals of retribution found in popular uprisings of the period: this suggests that the tsar had internalized much of the imagery of popular culture; and his appropriation of its idioms may have helped to gain popular support for his public executions.