an emperor could now be chosen not only at Rome, but anywhere in the empire where sufficient legions were amassed. Nerva, like Galba, came to the throne by senatorial designation, after the violent death of the previous emperor, Domitian. Like Galba, Nerva had to deal with a revolt of Praetorians and like Galba, he had designated his successor by the traditional expedient of adoption. Galba, described by Tacitus as a feeble old man, had chosen a successor unable, due to his severity, to obtain the faith and the control of the troops. Nerva, instead, had consolidated his power by making a link between the throne and Trajan, who was general of the Upper Rhine legions and popular throughout the army. It is probable that Tacitus was a member of the imperial council in which Trajan was chosen to be adopted. Ideology In the first book of the Historiae, a speech put in the mouth of Galba makes clear Tacitus' ideological and political position. Galba's pure respect for formality and lack of political realism rendered him unable to control events. In contrast, Nerva adopted Trajan, who was able to keep the legions unified, to keep the army out of imperial politics, to stop disorder among the legions, and thus to prevent rival claimants to the throne. Tacitus was sure that only the principatus (the "prince", that is, the monarchical emperor) could maintain peace, the fidelity of the armies, and the cohesion of the empire. Discussing Augustus Caesar's rise to power, Tacitus says that after the Battle of Actium, the unification of the power in the hands of a prince was necessary to keep the peace. The prince ought not to be a tyrant, like Domitian, nor a fool, like Galba. He should be able to keep the imperium safe, while saving the prestige and the dignity of the Senate. (Seneca addresses the same point). Tacitus considered the rule of the adoptive Emperors the only possible solution to the problems of Empire. Style The style of narration is rapid, reflecting the speed of the events. The narrative rhythm leaves no space to slow down or digress. To write effectively in this style, Tacitus had to summarize substantial information from his sources. Sometimes he skips parts; more usually he divides the story into single scenes and, in this way, creates a dramatic narration. Tacitus is a master at describing a mass of people.