John C. Yardley and Anthony Barrett (eds), Oxford World's Classics: Tacitus: The Annals
Kings first governed the city of Rome; liberty and the consulship were established by Lucius Brutus.* Dictatorships were employed to meet crises. The rule of the decemvirs* lasted no more than two years, and the consular authority of the military tribunes* was also short-lived. The ascendancy of Cinna* was not of long duration, nor that of Sulla; and the dominance of Pompey and Crassus* swiftly passed to Caesar, the armed might of Lepidus and Antonius to Augustus. Augustus then brought a world exhausted from civil dissension under his authority, with the title of 'First Citizen'.
The Roman people of old had their successes and their failures related by famous authors; and there was no shortage of fine minds for recording the Augustan period, until the groundswell of obsequiousness frightened them off. The histories of Tiberius, Gaius, Claudius, and Nero were distorted because of fear while they reigned, and, when they were gone, were composed with animosities still fresh. Hence my decision to deal only briefly with Augustus—and specifically with the final days—and then to move on to the principate of Tiberius and its aftermath, without rancour or bias,* far removed as I am from motives for these.