. . . is an invaluable source for the study of Roman history during the early Principate. Despite having provided us with information on the, shall we say, eccentricities of the emperors Suetonius' biographies offer a largely objective view of his subjects. A great deal of information concerning the emperors is provided, both bad and good, and Suetonius provides it without adding any personal judgement on the emperors and without adding the moralizations which are common in classical biography.

Furthermore, the focus on specific topics within the biographies such as building operations or the public entertainments can be used, in comparison with other sources, to show that Suetonius was comparing his subjects against an ideal standard of imperial behavior which had already become set by the time of the Caesares were composed. Thus Tiberius gets low marks while Nero and Domitian are commended for having successfully meeting some of their imperial responsibilities (though his final judgement on Nero and Domitian was damning). Suetonius was attempting to provide a realistic picture of the performance and personality of subjects based on then current standards. Thus what he says, and how he says it, are of great importance.