From Augustus on, as Cassius Dio noted, politics had ceased to be 'public'. The most fascinating source of the information about the Julio-Claudians is to be found in the surviving portions of Tacitus' Annals. Tiberius' first reported action after Augustus' death was to write to all the Roman armies. By inheriting the imperial household, the domus Caesaris, Tiberius controlled greater material resources than were available to any other Roman, either in a private capacity or as a magistrate. A number of the peculiar stories told about Gaius Caligula suggest that, more clearly than other emperors, he saw that the emperor's role symbolized the struggle of man against nature. Most ancient sources treat Claudius as a fool who became emperor by accident. Like other Romans excluded from politics, Claudius turned to intellectual pursuits, and in particular to the study of history. Like Caligula and Claudius at their accessions, Nero promised a new start, and a return to the principles of Augustus.