It is hardly unexpected that the praetorian guard, in immediate proximity to the emperor at the heart of imperial power, played an important role in bringing emperors to power and overthrowing them. However, it often proved less successful in maintaining them in the face of opposition from other elements of the army.
The whole force was concentrated in a single camp in Rome in 23 ce, by Aelius Sejanus, Tiberius’ praetorian prefect (Tac. Ann. 4.2), whose career provides a case study in the power an ambitious commander might wield. Similar, later, figures include Tigellinus under Nero and Septimius Severus’ praetorian prefect, Plautianus. However, for present purposes we should distinguish between the actions of individual commanders and those of the praetorians collectively.
Initially the praetorians were recruited directly from the civilian population of Rome itself and central Italy (Tac. Ann. 4.5). Dio indicates that until the reign of Septimius Severus most came from Italy, Spain, Macedonia, and Noricum (74.2.4-5). Septimius disbanded the existing guard (which had opposed him) and replaced its members with former legionaries, most of them from the Balkan legions that supported him (Peachin, this volume). A second body of guards, the cavalry equites singulares, was established probably by Trajan and coexisted with the praetorians (M. P. Speidel 1994). The latter were finally disbanded altogether by Constantine in 312 CE, because they had supported his rival, Maxentius (Zos. 2.9.3; 7.2).
We see the initial political power of the guard in the accession of Claudius (Suet. Claud. 10; Dio 60.1.1), allegedly found hiding in the palace by a guardsman on the death of Gaius, carried off to the praetorian camp, and acclaimed emperor. This acclamation was reinforced by Claudius’ payment of a 15,000 sesterces (3,750 denarii) donative, making him, according to Suetonius, the first emperor to buy the loyalty of his troops. The relationship of Claudius and the guard is strikingly portrayed in a series of gold and silver coins (RIC 1,122-3, pl. 15, nos. 20, 23) depicting the receptus (acceptance) not only of Claudius by the guard but also of the guard by Claudius. The guard played a crucial role in the accession of Otho (Suet. Otho 4-8) and famously succumbed to the bidding of Didius Julianus in the ‘‘auction’’ of empire conducted at the praetorians’ camp in 193 CE after their overthrow of Pertinax (Dio 73.11; cf. Herod. 2.6; Peachin, this volume). Even when an emperor was not directly chosen by the praetorians, their participation was important in consolidating and retaining power. Tacitus describes how Nero emerged from the palace on his accession, was carried by the duty cohort to the praetorian camp on a litter, offered a donative, and was hailed emperor (Ann. 12.66).
Likewise the praetorians might exercise an influence on internal politics to the advantage or detriment of the reigning emperor. While Tiberius showed senators the praetorians at drill, according to Dio, to intimidate them, in 97 ce they forced the ruling emperor Nerva to execute individuals implicated in the death of Domitian (Dio 57.24; 68.3.3-4; Peachin, this volume). In the reign of Severus Alexander, the praetorians murdered Ulpian, the praetorian prefect, and fought running battles with the civilian population of Rome for three days (Dio 80.2.2-4).
However, the praetorians often proved less effective in maintaining their chosen emperors in power. The guards who brought Otho to power do not seem to have been very effective in fighting for him against Vitellius’ Rhine legions, and Tacitus (Hist. 2.18-19) notes their indiscipline and inexperience. Likewise Didius Julianus’ praetorians were ineffective against Septimius Severus, allegedly because they had ‘‘learned to live luxuriously’’ (Dio 73.16.3). Similarly Maxentius’ infantry (presumably including the praetorians) seems to have been less enthusiastic than his cavalry when fighting for him against Constantine (Zos. 2.16.3-4).
The praetorian guards also put an end to the reigns of several emperors. Although Pertinax had promised them a donative of 3,000 denarii on his accession, nevertheless they killed him within a few months (Dio 73.1.2, 8.1-10.2; HA Pert. 4.6; Herod. 2.4.4-5). Likewise Elagabalus was murdered by praetorians in 222 ce (Dio 79.20; Herod. 5.8.5-9), and Pupienus and Balbinus in 238 ce (Herod. 8.8.4-7).
World History
