Tacitus, a Roman senator writing in the early second century, composed the Annals, his history of the emperors after Augustus. This is Book 6. What survives of Book 5 is a fragment: Sejanus, commander of the emperor’s bodyguard, is still at his height, then the pages tear in the middle of his fall. We resume in Italy, with Tiberius still on the throne.

In 37 Tiberius dies at Misenum, a harbor near Naples, amid stories that he was smothered when a last breath seemed to return. The public mix hatred, fear, and a relief they dare not shout. Macro, the new prefect of the Guard — the emperor’s household troops — manages the deathbed and backs Gaius Caesar, called Caligula, son of the popular general Germanicus. Rumors from the island of Capri have already stained the old man. Sejanus’s fall did not restore liberty. One-man rule and suspicious justice outlasted the favorite. Aristocrats survive by silence and flattery. Tacitus leaves this stretch of Tiberius in exhausted fear; the next books, which would have given Caligula whole, are lost.