Tacitus' Historiae begin in the middle of a series of civil wars: initium mihi operis Servius Galba iterum Titus Vinius consules erunt. This point of time leaves the revolts of Vindex and Galba behind and the revolts of Otho and Vitellius just about to begin. Such a plunge in medias res, more suitable for the novelist than the historian, was at one time sharply criticized. It would have been more logical, it was argued, to begin with the proclamation of Galba at the beginning of April A.d. 68, with the death of Nero on 9 June following, or with the death of Galba himself on 15 January A.d. 69. These points, or others even earlier or later, are better ‘natural breaks’ in the story, and consequently more satisfactory from the literary point of view than the arbitrary breaks of the calendar. On behalf of Tacitus it was maintained that in Roman historiography the annalistic method had the force of law (but what then of the starting-point of the Annales—ab excessu divi Augusti?), or that Tacitus took up the tale where some other historian, Cluvius Rufus perhaps or Fabius Rusticus, had left off (why then the long introduction extending to ch. II? Xenophon, for example, felt no such need for the Hellenica). Tacitus himself does not attempt to justify his choice of starting-point. In fact the use of the future tense (erunt) may be thought to imply that the matter is scarcely worth discussing at all. That was likely, I think, to have been Tacitus' hope and intention. If it was so, it has been realized in the most recent scholarship, which, having failed to make out a conclusive case for or against any other date, has fallen back on the belief that 1 January A.d. 69 was, faute de mieux, inevitable.
