Besides the confidence a few Caesars like Tiberius had in astrology, the ability of individuals to predict the future through the interpretation of dreams and unusual events is an important element in every biography in The Twelve Caesars. Major events, like the deaths of every Caesar, the end of the Julio-Claudian dynasty, and Vespasian’s rise to power, are foretold, according to Suetonius. For instance, Suetonius claims that before Otho died, he had a nightmare and, in the morning, was found “seeking to propriate with every possible rite the shade of Galba, by which he had dreamt he was ousted and expelled” (“Otho,” Section 7).

The Romans believed the universe was orderly and interconnected. Much like how one could predict the movement of the planets through observation and mathematics, the Romans believed omens and dreams could reveal significant pending events, such as the death of an influential figure. Like each Caesar’s aristocratic background, the omens illustrate the Caesars’ historical significance and proved that they fulfilled a preordained role.

The most significant question Suetonius poses throughout The Twelve Caesars is what makes a ruler tyrannical or virtuous. Suetonius believed that the traits that made an emperor virtuous or tyrannical were innate and unchanging from childhood to death.