by the state. As Tacitus vividly describes, However, Tacitus' portrayal of a tyrannical, vengeful emperor has been challenged by some historians: Edward Togo Salmon notes in A history of the Roman world from 30 BC to AD 138: While Tiberius was in Capri, rumours abounded as to what exactly he was doing there. Suetonius records the rumours of lurid tales of sexual perversity, including graphic depictions of child molestation, and cruelty, and most of all his paranoia. While heavily sensationalised, Suetonius' stories at least paint a picture of how Tiberius was perceived by the Roman senatorial class, and what his impact on the Principate was during his 23 years of rule. Final years The affair of Sejanus and the final years of treason trials permanently damaged Tiberius' image and reputation. After Sejanus's fall, Tiberius' withdrawal from Rome was complete; the empire continued to run under the inertia of the bureaucracy established by Augustus, rather than through the leadership of the Princeps. Suetonius records that he became paranoid, and spent a great deal of time brooding over the death of his son. During this period there was a short invasion by Parthia, and incursions on Roman territories by Dacian and Germanic tribes. Little was done to plan or secure Tiberius' succession. The Julians and their supporters were diminished in numbers and political influence, thanks to Sejanus, and Tiberius' immediate heirs were dead. Caligula, the sole surviving son of Germanicus, or Tiberius' own grandson, Tiberius Gemellus, were possibly candidates. However, Tiberius only made a half-hearted attempt at the end of his life to make Caligula a quaestor, and thus give him some credibility as a possible successor, while Gemellus himself was still only a teenager and thus completely unsuitable for some years to come. Death Tiberius died in Misenum on 16 March AD 37, some months before his 78th birthday. Tacitus relates that the emperor appeared to have stopped breathing, and that Caligula, who was at Tiberius' villa, was being congratulated on his succession to the empire, when news arrived that the emperor had revived and was recovering his faculties. Those who had moments before recognised Caligula as Augustus fled in fear of the emperor's wrath, while Macro took advantage of the chaos to have Tiberius smothered with his own bedclothes. Suetonius reports several rumours, including that the emperor had been poisoned by Caligula, starved, and smothered with a pillow; that recovering,