Why was the loyalty of the army and the Praetorian Guard the real foundation of the principate, and why did succession remain a recurring crisis?
The army, the Praetorian Guard and imperial succession: the role of the legions and the Praetorians in making and unmaking emperors, the lack of a fixed succession rule, the use of adoption and marriage, and how these structural problems shaped the whole Julio-Claudian period.
An OCR A-Level Ancient History period study guide to the army, the Praetorian Guard and imperial succession under the Julio-Claudians. Covers the role of the legions and Praetorians in making and unmaking emperors, the absence of a fixed succession rule, the use of adoption, marriage and donatives, and how these structural problems shaped the whole period from Augustus to Nero.
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What this dot point is asking
Running through the whole Julio-Claudian period is one structural theme: the army, the Praetorian Guard and the problem of succession. This page draws the theme together: the role of the legions and the Praetorians in making and unmaking emperors, the absence of a fixed succession rule, the use of adoption, marriage and donatives, and how these structural problems shaped the period from Augustus to Nero. It is a synoptic topic that rewards an argument across the whole period, ideal for the 20-mark essay.
The answer
The army as the foundation of power
This is the synoptic thread: every emperor's security ultimately rested on the soldiers, which is why the army repeatedly decided who ruled.
The problem of succession
The absence of a succession rule is the structural flaw that connects the reigns: the murders, adoptions and remarriages that fill the period (Agrippina's manoeuvres for Nero, the fate of Britannicus) all flow from it.
The Guard, the donative and the secret of empire
The role of the Praetorian Guard makes the point concrete:
- In AD 41 the Praetorians murdered Gaius and then proclaimed Claudius, paying him a donative, an open demonstration that the Guard could make an emperor.
- Under Tiberius, Sejanus's near-seizure of power showed the danger of the praetorian prefecture.
- In AD 68 the provincial armies revolted and the Guard abandoned Nero, ending the dynasty and revealing what Tacitus called the "secret of empire": that an emperor could be made outside Rome by the legions, the lesson confirmed in the civil war of AD 69.
Constitutional powers, dynastic legitimacy, the Senate and wealth all shaped how power was exercised and legitimised, but the army was the ultimate arbiter.
Examples in context
A model answer argues synoptically across all five reigns and ranks army loyalty against the constitutional and dynastic factors.
Try this
Q1. Assess how far the lack of a clear succession rule was a source of instability under the Julio-Claudians. [20 marks, period essay style]
- What the marker wants. A synoptic AO1 and AO2 argument that the absence of a fixed succession forced improvised arrangements (adoption, marriage, grants of power) and recurring intrigue and murder across the reigns, weighed against other sources of instability, with a judgement and source evaluation.
Q2. What did Tacitus mean by the "secret of empire" revealed in AD 68 to 69? [2 marks]
- Cue. That an emperor could be made outside Rome by the provincial armies, not only by the Senate or the Praetorians in the capital, exposing the army as the true maker of emperors.
Exam-style practice questions
Practice questions written in the style of OCR exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
OCR H407/21 202020 marks'Throughout the Julio-Claudian period the loyalty of the army was the true basis of imperial power.' Assess how far you agree. [shown at the 20-mark period essay cap]Show worked answer →
A Section A 20-mark period essay (AO1 and AO2). Reach a judgement across the period.
For the view. Augustus's power rested on control of the armed provinces; the Praetorians proclaimed Claudius and were paid a donative; Nero fell when the armies and the Guard abandoned him in AD 68; the "secret of empire" (that an emperor could be made outside Rome) was revealed in AD 69.
Other factors. Constitutional powers, dynastic legitimacy, the support of the Senate and the people, and wealth and patronage also mattered.
Judgement. The strongest answers argue that army loyalty was the ultimate foundation (it made and unmade emperors), while the other factors shaped how that power was exercised and legitimised. The top level judges across the whole period and evaluates the sources.
OCR H407/21 202212 marksHow useful is Tacitus for understanding the role of the Praetorian Guard in imperial succession? [shown at the 12-mark source-utility cap]Show worked answer →
A Section A 12-mark source-utility question (AO3).
Value. Tacitus is acute on court and military politics, valuable for the Praetorians' role (the proclamation of Claudius, the donatives, the prefects such as Sejanus and Burrus) and for the insecurity of the succession.
Limitations. Tacitus writes with senatorial hindsight and a moralising agenda hostile to the emperors and to the Guard's power; he interprets events to expose the corruption of the principate, so his framing must be allowed for; for the proclamation of Claudius the fuller account is in Josephus and Dio.
Judgement. Highly useful for the politics of succession and the Guard's power, but his senatorial bias and interpretation must be weighed. Top answers judge usefulness for the enquiry.
Related dot points
- Augustus and the creation of the principate: the settlements of 27 BC and 23 BC, proconsular imperium and tribunician power, the language of the restored Republic, the Res Gestae, and the foundations of one-man rule.
An OCR A-Level Ancient History period study guide to Augustus and the creation of the principate. Covers the settlements of 27 BC and 23 BC, proconsular imperium and tribunician power, the fiction of the restored Republic, the Res Gestae as self-presentation, and the foundations of one-man rule, with evaluation of the Res Gestae, Tacitus, Suetonius and Velleius.
- Tiberius as emperor: his accession and relations with the Senate, the use of treason (maiestas) trials, the rise and fall of Sejanus and the retreat to Capri, and the problems of judging Tiberius given the hostility of Tacitus and Suetonius.
An OCR A-Level Ancient History period study guide to the reign of Tiberius. Covers his accession and difficult relations with the Senate, the growth of treason (maiestas) trials, the rise and fall of the praetorian prefect Sejanus and the retreat to Capri, and the problem of judging Tiberius given the hostility of Tacitus and Suetonius.
- Claudius as emperor: his accession through the Praetorian Guard, the administrative role of his powerful freedmen, the conquest of Britain in AD 43 and its propaganda value, his relations with the Senate, and the difficulty of judging him from divided sources.
An OCR A-Level Ancient History period study guide to the reign of Claudius. Covers his accession through the Praetorian Guard, the administrative power of his freedmen (Narcissus and Pallas), the conquest of Britain in AD 43 and its propaganda value, his relations with the Senate and his wives, and how the sources divide between mockery and respect.
- Nero as emperor: the guided early reign under Seneca and Burrus, the murder of his mother Agrippina, his artistic and Greek interests, the fire of Rome in AD 64 and the persecution of Christians, the conspiracies, and the revolt that ended the Julio-Claudian dynasty in AD 68.
An OCR A-Level Ancient History period study guide to the reign of Nero. Covers the guided early reign under Seneca and Burrus, the murder of Agrippina, his artistic and Greek interests, the fire of Rome in AD 64 and the persecution of Christians, the Pisonian conspiracy, and the revolt that ended the Julio-Claudian dynasty in AD 68, with evaluation of Tacitus and Suetonius.
- AO4 interpretation skills: analysing and evaluating the differing interpretations of modern scholars, understanding why historians disagree (evidence, method, emphasis), and weighing interpretations to reach a reasoned position.
An OCR A-Level Ancient History skills guide to analysing modern interpretations for AO4. Explains how to evaluate the differing views of modern scholars, why historians disagree (different evidence, methods and emphases), and how to weigh interpretations against the ancient evidence to reach a reasoned position, with examples from the Greek and Roman topics.
Sources & how we know this
- OCR A Level Ancient History H407 specification — OCR (2017)
- Tacitus, Annals and Histories 1; Suetonius, Lives of the Caesars; Cassius Dio — Perseus Digital Library