Tacitus, by contrast, appears to mark a clear turning point. After describing the first maiestas trials of the reign in early 62 he introduces the death of Burrus with the words, 'As the ills of the state grew worse, the forces for good were declining'. The death of Burrus, he explains, broke Seneca's power and Nero now listened to evil advisers while Seneca tried to withdrew from public life. Tigellinus, one of Nero's new Prefects of the Guard, grew in influence day by day and succeeded in making the Emperor his collaborator in crime.4 Explicit statements make it clear that Tacitus
Cassius Dio, like Suetonius and Tacitus, holds that Nero had a natural inclination to vice. In his view, indulgence began at once, and Seneca's and Burrus' policy of allowing him to gratify his desires, as long as they did not damage public interests, only encouraged his passions. Although Dio's account is only partially preserved at this point, the principal stages of Nero's decline are clearly marked in what survives. First there is the murder ofBritannicus in 55, which led Seneca and Burrus to limit their efforts to routine government and self-preservation; then, the death of Agrippina in 59, after which Nero lost all sense of right and wrong and listened to flattery with total credulity.6 Dio's most thorough editor divined that his two Neronian books were divided so as to mark the importance of this second stage, Book LXII starting with the year 59.7
Tacitus also begins a new book at that point and indeed makes explicit the significance of Agrippina's removal for Nero's conduct: 'He plunged into all the excesses which a certain regard for his mother had up to now retarded but not entirely controlled' (XIV. 13). In this analysis, Tacitus and Dio were following a tradition that had taken shape even before Nero's death, as Tacitus' own narrative makes clear. In recounting the uncovering of the Pisonian conspiracy in the spring of65, Tacitus claims to give verbatim the reply of the praetorian tribune Subrius Flavus who was asked by the Emperor why he had betrayed his oath ofloyalty: 'I began to hate you after you murdered your mother and your wife, and became a charioteer, an actor and an arsonist' (xv. 67). If we allow that October 54 to March 59 is roughly a quinquennium, we can see that this tradition, in a grossly exaggerated form, is the basis of the anecdote in which Trajan praises a Quinquennium Neronis as incomparable and then goes on to talk about his later moral decline. Aurelius Victor and the author of the Epitome de Caesaribus identified the period as the beginning of the reign, on the basis of this well-known tradition. They then attempted to justify Trajan's praise with building works and provincial annexations for which Nero was indeed famous, but which, did they but know, fell mostly outside the first five years. 8 Tacitus knew better and saw the five-year period as more negative in character-a relatively innocent time-and chose to concentrate on the year 62 when Nero began to break early pledges and carry his crimes outside his immediate family.