This article deals with the history and historical memory of medieval Russia. Because sources written after the death of Ivan the Terrible (1533-1584) figure prominently in historical studies of his life and times, the accuracy of information about him in Muscovite historical memory is a vital concern. Meanwhile, no one has systematically posed this question as far the corpus of relevant sources as a whole is concerned. A comprehensive survey reveals that late sixteenth-and seventeenth-century Muscovite texts contain a significant number of historical errors. This article discusses the extent to which errors in later sources reflect ignorance of sixteenth-century Russian history. Authorial ignorance of Ivan's reign must be taken into account in evaluating these sources. The author draws the conclusion that ignorance of Ivan's reign in Muscovite historical memory was far greater than has been appreciated. This situation may be connected with a common feature of Russian culture: Muscovy remained a manuscript culture at this time. But the author draws another conclusion: this ignorance was probably not a product of Muscovy's failure to join the Print Revolution. The virtual absence of print technology in Muscovy might not have been the cause of ignorance of the reign of Ivan Groznyi in Muscovite historical memory. The author "tentatively" formulated the following five observations: the transition to print was a process, not a rapid "revolutionary" change; typographical errors replaced scribal errors; bias, both dynastic and religious, dominated interpretations even in relatively accurate histories; Printing did nothing to eliminate ancient myths and legends in historiography; although printing could generate myths and legends about more recent rulers, it is possible that printed histories avoided the most fantastic myths and legends about more recent history. Historical memory is always selective, and errors of omission are just as erroneous as errors of commission.