Tiberius Booklet 1



Roman magistrate whose duties included maintaining the city of Rome and arranging public festivals and games.


Head of government during the Republic. Two elected each year. During Principate, more of a stepping stone to commands in the provinces/army.

Comitia Curiata

Assemblies of the Roman people, sitting and voting in their parishes (curiae).

Cursus Honorum

The ladder of office climbed by senators in their quest for the consulship. Progress was affected by the emperor’s favour (or lack or it!)


A prosecutor/informer in the treason trials


Members of Rome’s second class. Also known as “knights”.


Originally a military title given to the equivalent of a commander. Came to be used as a title by emperors.


Supreme authority. The “power to do something”. Bestowed on consuls and praetors. Superior form held by the emperor.


A roman magistrate whose duties were chiefly financial (supervised treasury, paid army, collection of tax in provinces)

Pater Patriae

Father of the Country


Traditionally the oldest part of Rome’s aristocracy.


Common people, lower classes


Second most important office after the consulship. Led to legionary commands and/or governments of second-rank provinces.

Praetorian Guard

The emperor’s bodyguard


“First citizen” – a term of address but did not imply a particular office.

Proconsular Imperium Maius

Imperium in the provinces that is greater “maius” than that of anyone else.

Provincial Governor

Senators or Knights who ruled the provinces of the Roman empire.

Recusatio imperii

The ritual refusal of power by a new emperor (i.e. by Augustus and Tiberius to the senate)


Council of nobles forming part of the political institution of Rome. Advisory body to the emperor.

Tribunician Potestas

Having the power of a Tribune – traditionally those responsible with defending their fellow Plebeians against Patrician injustice. They could call the Senate, introduce legislature and veto decisions.


It is also useful to know how upper class Roman names work. An upper class Roman had three names:

  1. Praenomen (personal name) of which there was about thirty e.g. Quintus, Titus, Lucius, Tiberius, Marcus etc
  2. Nomen (clan or “gens” name) of which there were thought to have been about a thousand. Examples include Claudius (Claudian clan), Julius (Julian clan) and Cornelius (Cornelian clan)
  3. Cognomen (family name), which indicated the particular branch of the clan to which a man belonged. Within the Cornelian clan, there were families with names like Scipio, Sulla & Gallus. Sometimes a cognomen was an obvious reference to a particular physical/mental peculiarity e.g. Caesar (curly haired).

Augustus’ Legacy


1.      Name the three men that Augustus’ daughter Julia was forced to marry

a.       Marcus Claudius Marcellus

b.       Agrippa

c.        Tiberius


2.      What was the relationship of Germanius to Augustus and to Tiberius?

a.       Grandson-in-law and great nephew of Augustus

b.       Nephew and adoptive son of Tiberius


3.      List the women descended directly from Augustus who were mothers of future emperors.

a.       Julia Major

b.       Vipsania Agrippina II (Agrippina Major): Mother of Caligula

c.        Julia Agrippina (Agrippina Minor): Mother of Nero

4.      What was the exact relationship of each of the emperors Tiberius, Gaius (Caligula), Claudius and Nero to Augustus? Which ones were Julian (descended directly from Augustus?) and which were Claudian (descended from Augustus’ wife Livia and her first husband, Tiberius Claudius Nero)?

a.       Tiberius: Step son

b.       Caligula: Grandson

c.        Claudius: Grandson of Augustus' second wife Livia, from her first marriage.

d.       Nero: Son of Agrippina, who was the great-granddaughter of the Augustus.


5.      What was the relationship between Gaius (Caligula) and Claudius and between Claudius and Nero?

a.       Caligula nephew of Claudius

b.       Nero was the son of Claudius’ first wife, Agrippina the Younger (Caligula’s sister) and Augustus’ adoptive son.


6.      Explain why Agrippa the Younger would have wanted to murder Britannicus (he was killed in AD55).

a.       So that her own son Nero could become Emperor


Remember that Tiberius was not Augustus’ first choice for the next emperor. Name his previous choices below and their relationship to Augustus.

1.      Marcus Claudius Marcellus

a.       Years of birth and death: 42BC – 23BC.

b.       Links to Augustus: Married to Augustus’ daughter Julia, and also his nephew.

c.        What happened to him: Died young, 19, cause unknown.


2.      Marcus Vispanius Agrippa

a.       Years of birth and death: 63BC – 12BC

b.       Links to Augustus: Right hand man and general who won Battle of Actium. Married to Augustus’ daughter Julia. Would have acted as regent until their grandsons were old enough.

c.        What happened to him: Dies of sickness in winter, aged 51.


3.      Gaius Caesar

a.       Years of birth and death: 20BC – AD4

b.       Links to Augustus: Grandson – son of Julia and Marcus Agrippa. Adopted by Augustus from 17BC.

c.        What happened to him: Fell ill whilst on a mission in East. Attempted to return home but died on the way.


4.      Lucius Caesar

a.       Years of birth and death: 127BC – AD4

b.       Links to Augustus: Grandson – son of Julia and Marcus Agrippa. Adopted by Augustus from 17BC.

c.        What happened to him: Wounded during siege in Marseilles. Speculation murdered by Livia.


5.      Tiberius

a.       Years of birth and death: 42BC – AD37.

b.       Links to Augustus: Stepson (mother was Livia) and adopted son of Augustus from AD4. Third husband of Augustus’ daughter, Julia. Intended to be regent for their sons.

c.        What was Augustus’ opinion of Tiberius?

                                                               i.      Adopted him reluctantly.

                                                             ii.      Makes him joint heir with Agrippa Postumus.

                                                           iii.      Saw him as a capable general and Suetonius remarks that Augustus says good outweighs the bad.

                                                           iv.      Makes him adopt Germanius (Augustus’ nephew w/ Julian blood).


Timeline of Augustus

63 BC

Augustus is born in 63BC to Gaius Octavius and Atia, niece of Caesar. He isn’t Augustus at the time, but Octavian.

48 BC

Caesar wins the Battle of Pharsalus, defeating Pompey, who flees to Egypt where he is killed. On October 18, Octavian (young Augustus) puts on the toga virilis: Octavian is officially a man.

45 BC

Octavian accompanies Caesar to Spain for the Battle of Munda.

44 BC

March 15 – Caesar is assassinated. Octavian is adopted in Caesar’s will.

43 BC

August 19 – Adoption of Octavian (young Augustus) by Caesar is officially acknowledged. Octavian becomes Gaius Julius Caesar Octavianus.

November 27 – Second triumvirate. Proscriptions of at least 100 senators including the execution of Cicero.

42 BC

January 1 – Caesar is deified and Octavian becomes the son of a god.

October 23 – Battle of Philippi – Antony and Octavian avenge Caesar’s assassination.

39 BC

Octavian marries Scribonia, the daughter of Sextus Pompeius, with whom he has a daughter, Julia.

38 BC

Octavian divorces Scribonia and marries Livia.

37 BC

Antony marries Cleopatra.

36 BC

Octavian defeats Sextus Pompey at Naulochus, in Sicily. Lepidus is removed from the Triumvirate. This puts the power into the hands of two men, Antony and Octavian.

34 BC

Antony divorces Octavian’s sister.

32 BC

Rome declares war on Egypt and puts Octavian in charge.

31 BC

With the help of Agrippa, Octavian defeats Antony at Actium.

30 BC

Cleopatra and Antony commit suicide.

29 BC

Octavian celebrates triumph in Rome.

27 BC

January 16 – Octavian receives the title Augustus. Augustus receives proconsular power in Spain, Gaul, Syria and Egypt.

25 BC

Augustus’ daughter Julia marries Marcellus (Octavian’s nephew).

23 BC

Augustus receives imperium maius and tribunicia potestas. These give power over magistrates and the veto.

Marcellus dies. Augustus has Agrippa divorce his wife to marry Julia. Julia and Agrippa have 5 children: Gaius, Lucius, Postumus, Agrippina and Julia.

22-19 BC

Augustus travels to the East. Augustus is initiated into the Mysteries of Eleusis and recovers Roman standards captured by the Parthians.

17 BC

Augustus adopts Gaius and Lucius.

Augustus legislates marriage laws.

May 31 – June 3 – Augustus celebrates the Ludi Saeculares

13 BC

Agrippa becomes virtual co-emperor, then goes to Pannonia where she becomes ill.

12 BC

Agrippa [a dies. Augustus forces his stepson Tiberius to divorce his wife in order to marry Julia.

March 6 – Augustus becomes Pontifex Maximus.

5 BC

January 1 – Gaius is presented as Augustus’ heir.

2 BC

January 1 – Augustus becomes pater patriae, father of his own country.

Julia is involved in scandals and Augustus exiles his own daughter.

 4 AD

Augustus adopted Tiberius and Tiberius adopts Germanicus

9 AD

Teutoburger Wald disaster – Varus suffers crushing defeat at hands of Germanic tribes.

13 AD

April 3 – Tiberius becomes virtual co-emperor.

14 AD

Augustus dies.


Recap of the Cursus Honorum “ladder of offices”

(Career ladder for Roman Politicians)

Whilst looking at Tiberius’ early life, you will have noted that he held a number of political offices or magistracies in Rome. A magistrate was an elected government official, occupying a position of power and prestige, both of which increased with the rank of his office. However, before a young man started on a political career he was expected to have spent at least ten years in some military position.  The regular magistrates, in ascending order were:

·       Quaestor

·       Aedile (can be by-passed)

·       Praetor

·       Consul

Certain essential requirements were laid down, including minimum ages for the various offices, a two year interval between the holding of consecutive offices and a ten-year interval between the holdings of the same office. This law made sure that those who reached high office had the necessary qualifications in both military and political affairs.




Minimum Age

Number elected annually


Financial official. Maintained records, supervised treasury, dealt with tax in the provinces etc.

30 (lowered to 25 by Augustus in



In charge of the public order in Rome. Dealt with riots, water supply, buildings, public games etc.




Legal post. Ran the law courts.




Top office of state. Commanded army, conducted elections, presided over senate and implemented their decisions.

42 (40 for Patricians)



Recap of Roman Society

Roman society was built around a class system that dated back to the founding of Rome. There were three main classes: Patricians, Equestrians and Plebeians. These classes were not equal and the richer citizens controlled society – and Oligarchy. The distinction between these could sometimes be blurred, and the relationship between the classes changed over time e.g. inter-marriage. However each had a role in society and there were certain rules that applied to each.





Wealthy and powerful.

Entitled to own a public horse.

No status.

Property of owner.

Extra legal status.

Economic and public trade.

Cn only move up half the political ladder.

1/3 Romans slaves.

1/3 Slaves black.

Can own slaves.

Chosen by emperors to govern imperial provinces.

Aedile highest role they can achieve.

Children can be born into slavery.

Born into power.

Praetorian prefects.

Official Roman citizens.

Manumission – buying their way out.

Only class allowed to be part of senate.

Not allowed to be senators.


Augustus used freed men as civil service.

Cannot marry plebeians.

Head of praetorian guard.


Mines/building/public staff.


Cavalry and merchant class.




Positives of Tiberius becoming emperor

Problems associated with accession

Appointed provincial governor at 25 – governing experience.

Not emotionally stable – divorce from first wife.

Experience commanding armies.

Had been retired for many years before returning to Rome.

Husband of a Julian (Julia).

Not favoured by Augustus – not his first choice as heir.

Trusted by Augustus to act as a guardian to his heirs at the time, Gaius and Lucius.

Questionable personal life – little fishes.

Adopted by Augustus.

Divorced from Julia – no longer linked to Julians.

Respectful of Augustus after his death.

Not trusted with complete heirship – shared with Postumus.

Divorce of first wife to marry Julia – loyal to Rome (although not much choice).

Didn’t build many public work projects.

Diplomacy skills – retrieved the standards lost by Crassus.

Suspicion surrounding his succession.

Consulship at 28 – min age 42.



Introduction to our first historical source: Suetonius.


Suetonius was writing during the reign of Hadrian and was the emperor’s secretary. His career was different to that of Tacitus (the other historian we will study) as he remained of equestrian status (a knight) and therefore did not enter the Senate. The era in which Hadrian was emperor is known as the period of the “adoptive emperors” (chosen on merit not birth) and therefore part of Suetonius’ motive for writing was to please Hadrian by justifying the rejection of the principle of hereditary monarchy. This is why there is a tendency to emphasise the drawbacks of the hereditary principle, without criticizing the idea of a princeps as such. Hereditary monarchy means a lottery at birth – you might end up with someone decent e.g. Titus but you are more likely to end up with a Caligula, Nero or Domitian.  



His biographies are complete so we have plenty to go on.


More concerned with emperors’ personalities and behaviour than with major political and military events during their reigns.


We are able to use his biographies to make comparisons between portrayals of emperors e.g. Tiberius and Claudius.


Written after the events/individuals.


Access to archives as he is employed by emperor Hadrian.

Still writing under an imperial system so his views may be influenced by this.


Uses eye witness accounts.

Too much emphasis on anecdotes (although actual documents referenced in places) – is not sufficiently critical enough of his sources, therefore leading to unsubstantiated gossip/scandal.


Follows a clear formula that provides a structure to his biographies: starts with family background and early life and ends with character and physical appearance as this approach lends itself to a depth of insight on character.

Archived material cannot contain much evidence for an individual’s motivation and/or character?

Formulaic approach is possibly limiting

Despite not moralising, arranges his material with the negative points last (leading the reader to certain impressions).



Does not moralise; presents his material and leaves the reader to make up their own mind

Includes anecdotes (stories/narratives) for interest.

Possible bias as a result of writing to please Hadrian by justifying the rejection of a hereditary monarchy.


Useful in conjunction with fellow historian, Tacitus.

Also uses a great number of Greek technical terms which was considered bad style on Latin literary writing.


Independent Reading Task:

Read Suetonius’ account of Tiberius’ early life and answer the questions that follow. Note that the number next to each question related to the paragraph of Suetonius’ Tiberius that you will find the answer in.

1.       How old was Tiberius when his father died? What task did Tiberius perform at his father’s funeral? (6)

a.       9.

b.       Delivered the eulogy.

2.       Who was the father of Vipsania, Tiberius’ first wife? Why did Tiberius strongly disapprove of Julia, who became his second wife? (7)

a.       Marcus Agrippa.

b.       Still in love with Vipsania and only married Julia for political gain.

3.       When Tiberius retired to Rhodes, to give Gaius and Lucius a clear run, to whom does Suetonius compare Tiberius’ actions? (10)

a.       Marcus Agrippa.

4.       According to Suetonius, why was Julius banished in 2BC? (11)

a.       Immoral and adulterous behaviour.

5.       Give one example, from this paragraph, of an omen that predicted Tiberius’ eventual rise to power. (14)

a.       A bird, never before seen on the island, perched on top of his house.

6.       What did Tiberius spend three years doing, after his return to Rome?

a.       Conducted the supressing of the revolt.

7.       Tiberius visited Germany in 10AD, the year after Varus’ defeat, to investigate the reasons for the disaster. What was his verdict on the reasons for the massacre?

a.       Varus’ rashness and neglect for precautions against surprise. (18)

8.       What evidence was given to support the image of Tiberius ad a very “hands on” general? (18)

a.       Ate on bare turf.

b.       Slept in open air.

c.        Wrote all his orders down so that the legions would understand at all times what he wanted.

9.       What gossip does Suetonius repeat, that gives a very negative reason for Augustus’ choice of Tiberius as his successor? (21)

a.       “Poor Rome, doomed to be ground by those slaw moving jaws”.

10.   What does Suetonius quote from, to show that Augustus in fact rated Tiberius? (21)

a.       Augustus’ correspondence.


The Accession of Tiberius

The most important element of the accession to understand is that Augustus did not have any surviving direct male heirs and he had also not established a rule of succession. This meant that when Augustus died, his position could not be legally inherited and whilst ancestry or blood was important, it was not essential. The intended successor (Tiberius) could be threatened by rival candidates and it was therefore essential that he have the support of the Senate, the Praetorian Guard and the Army to stay in power.

As emperor, Augustus held a suite of powers that gave him the power of a magistrate without needing to actually hold that political position. These powers were:

·       Proconsular Imperium Maius (maius in Latin means “greater” so this meant that the emperor’s power over the provinces in the Roman Empire were greater than anyone else’s). This position also gave the emperor control of the army.

·       Tribunician Potestas. This was given to Augustus in 23BC when he resigned from the Consulship, thus losing the ability to legislate (law making). It allowed him to continue to call the senate and introduce and veto legislation but it was also very symbolic – the emperor is responsible for the safety of the Plebeians.

As the above were powers and not magistracies, it enabled the Senate to transfer these owers onto another individual after Augustus’ death and this is exactly what happened to Tiberius in AD14. However, at first he pretends to reject the offer of imperial power, exactly as Augustus had done in 27BC

The Principate of Tiberius


Became ruler on Augustus’ death.

Agrippa Postumus was strangled within weeks of Tiberius’ accession.

Mutinies within the Rhine and Danube legions (wanted a pay rise).


Sejanus becomes sole Prefect of the Praetorian Guard (this role was held by an equestrian as a senator could challenge for ultimate power).


Earthquake destroys cities in Asia Minor; Tacfarinas’ revolt begins in North Africa.

Germanicus given a triumph maius imperium.


Tiberius holds the consulship with Germanicus.


Death of Germanicus (Tiberius’ nephew and adopted son) at Antioch, Syria; Piso (Governor of Syria) is tried for his murder and commits suicide.


Tiberius grants Tribunician power to his son Drusus the Younger (Castor in I, Claudius) designating him as his heir in the wake of Germanicus’ death.


Death of Tiberius’ son, Drusus the Younger (poisoned by wife Livilla – Germanicus’ sister and her lover, Sejanus).


Tiberius took up residence in Capri, never returning to Rome.


Death of Livia (Tiberius’ mother); prosecution of Agrippina (Germanicus’ widow) and their two eldest sons Nero and Drusus.


Germanicus’ son Drusus is arrested.


Joint consulship of Tiberius and Sejanus (to make Sejanus think he had succeeded in becoming the heir); denunciation and execution of Sejanus on 18th October.


Death of Tiberius (smothered by Macro and/or Caligula?) on 17th March. Body brought back to Rome; cremated and ashes placed in the Mausoleum of Augustus. Not deified by senate.

Tiberius and His Family (Early on in Reign)

Germanicus Profile

Full name

Germanicus Julius Caesar.

Date and place of birth

24th April 15BC in Rome.


Drusus the Elder and Antonia the Younger


Livia and Tiberius Claudius Nero.

Octavia and Marc Antony.

Married to

Agrippina the Elder.


Nero, Drusus, Gaius Caligula, Agrippina Minor, Livilla, Drusilla.

Adopted by

Tiberius on the orders of Augustus in AD4.

Military experience

AD12 Command in Gaul and the Rhine.

AD14-16 Command across the Rhine.

AD14 Quelled mutiny in the rhine.

AD18 Supreme commander of the Eastern provinces.

Tour of East


Cappadocia and Commagene.


Incorporate Cappadocia and Commagene as provinces and install a new king in Armenia (land between Rome and Parthian empires).

Key events

Unauthorised visit to Egypt (Emperor’s province). Released the grain supplies and has coins cast in his own image, making him popular.



Illness or poisoned.


In Syria.



Who was blamed

Piso and/or wife Plancina. 


For Piso

Piso flees Syria after a breakdown in their relationship. Returns to take the province by force. Piso is prosecuted on return to Italy. He was tried and committed suicide.

For Tiberius

Drusus becomes his heir.

Never escapes suspicion of killing Germanicus.

Conflict between Tiberius and Agrippina (Germanicus’ wife).


Understanding Why Germanicus was a Threat to Tiberius

Germanicus was the son of Tiberius’ popular brother, Drusus the elder (who had died in 9BC). Both Suetonius and Tacitus paint a glowing picture of Germanicus with Suetonius commenting on his “outstanding physical and moral excellence” and Tacitus noting that had he lived “he would have equalled Alexander (the Great) in military renown as easily as he outdid him in clemency, self-control and every other good quality”. Tacitus also presents his wife, Agrippina as the most admirable and striking of Imperial women. Germanicus was immensely popular with the Roman people and the army – probably due to his lineage. Germanicus was partly Julian and his wife was the granddaughter of Augustus.

After quelling the mutiny in lower Germany, Tacitus tells us that Germanicus embarked on a number of campaigns across the Rhine from AD14-16, without the authority of Tiberius (and going against what had been Augustus’ foreign policy to maintain strong frontiers). He achieved only minor successes and suffered serious losses of men, ships and supplies. Despite Germanicus’ wishes to campaign for one more year, Tiberius instructed him to return to Rome and offered him a second consulship, as well as a diplomatic mission to the East to install a pro-Roman on the throne of Armenia. To keep Germanicus’ ambition in check, Tiberius arranged for Calpurnius Piso to take over the province of Syria and keep an eye on Germanicus. This was despite the fact that Germanicus, as a Consul, had Imperium and therefore control over all governors and commanders in the East.

Despite a successful diplomatic mission, Germanicus breached protocol on a number of occasions:

1.       Visited Egypt to look at the antiquities despite the law that no Senator could enter the province without the Emperor’s permission.

2.       Released grain from the public granaries without the approval and lowered the cost of grain.

3.       He had his image cast on silver coins.

Despite obviously having a good reason to keep an eye on Germanicus, Tiberius had made a bad choice in Piso as spy. Rather than simply reporting back, Piso made an enemy of Germanicus by cancelling or reversing his instructions and refusing to provide him with troops. Germanicus ordered Piso out of the province and Piso attempted to stir up the Syrian troops against Germanicus. Not long after Piso’s departure, Germanicus became ill and died, and Tacitus records that on his deathbed, Germanicus accused Piso and his wife Plancina of poisoning him. Following the death, Piso attempted to re-establish control of Syria by force (an illegal act) and when failed he sailed for Sicily where Agrippina accused him and Plancina of murdering her husband on the instructions of Tiberius.

Germanicus’ popularity is evident form the honours bestowed on him after his death and the triumphal arches, statues and inscriptions erected. Tiberius created hostility by not appearing at the funeral ceremonies and calling for moderation in mourning. Whilst there is no evidence that either Piso or Tiberius had anything to do with Germanicus’ death, Tacitus admits it was uncertain whether the body showed signs of poisoning.

Drusus the Younger Profile

Full name

Nero Claudius Drusus and later Drusus Julius Caesar.

Date and place of birth




Tiberius and Vipsania.


Livia and Tiberius.

Marcus Agrippa.

Married to with date of marriage




Julia, Tiberius Gemellus, Claudius Caesar.


AD2 – Introduced to public life.

AD15- Consul.

AD17-20 – Governor of Illyricum.

AD21- Share consulship with Tiberius.




Castor – the patron god of the Praetorian Guard. Ironic nickname after being I a fight with the guardsman.

Date and place of death



How did he die?


Who was blamed?

Sejanus and Livilla.

Outcome for Tiberius

He has no heir of age, therefore may look towards his advisor Sejanus more.

Germanicus’ sons were intrusted to care of senate.



Full name

Lucius Aelius Sejanus.

Date and place of birth

20 BC, Volsinii, Etruria.

Married to

Apicata (has an affair with Livilla).


Strabo, Capito Aelianus and daughter Junilla – all died during his downfall.

Social class


Family members

Father, Lucius Seius Strabo, was Praetorian Prefect before Sejanus.

Becomes joint Prefect with Sejanus.

When he retires, Sejanus remains the sole Prefect of the Praetorian Guard.


Accompanied Gaius Caesar on campaigns to Armenia in 1BC.

Appointed to co-Prefect.


Drusus the Younger – favourite to succeed Tiberius.

Sejanus eliminated Drusus with the help of Livilla.

Relationship with Tiberius

Relationship crucial to maintain power.

The more impressed with his abilities, the more dependent he was upon him.

Sejanus attempted to marry into the Julio-Claudian family but Tiberius refused.

Began to isolate Tiberius from Rome by fuelling his paranoia towards Agrippina and the senate.

Capri retirement – Sejanus becomes sole ruler of Rome.

Controls correspondence to and from Tiberius on Capri.


Main Sources

David Shotter – Tiberius (Shotter sees Sejanus as an arch-villain).
Thomas Wiedemann – The Julio Claudian Emperors (questions whether Sejanus was really responsible for all the crimes laid at his door).

The Praetorian Guard

At Augustus’ death in AD14, there were two joint prefects (commanders) of the Praetorian Guard – Lucius Seius Strabo and his son, Lucius Aelius Sejanus (both of whom were of equestrian i.e. knight status) Tiberius then made Sejanus sole prefect when his father become Prefect of Egypt.

The Praetorian Guard were the only Roman troops actually stationed in Italy – the legions and auxiliaries were garrisoned in the provinces, to keep the peace, to avoid armed insurrection in Rome itself, and to avoid giving the impression of a military dictatorship. The Praetorian Guard consisted of 9 cohorts of 1000 men each, giving a total strength of 9000 men. Under Augustus, the Praetorian Guard had been billeted in the small towns around Rome (in order to keep a low profile). Augustus also ensured that there should always be two prefects of the Praetorian Guard, who should always be equestrians rather than senators (s0 that they could pose no challenge to his own position as princeps).

Sejanus’ Background

Although he was “only” a knight, Sejanus was related to several families of senatorial/consular status. His uncle was Quintus Junius Blaesus, who was Governor of Pannonia and commander of its legions at the time of Tiberius’ accession (the same Blaesus who later become Governor of Africa and helped to squash Tacfarinas’ revolt). Sejanus was adopted by Quintus Aelius Tubero, which meant he had adoptive brothers of consular status.

Tacitus implies that Sejanus suddenly became important in AD23, which David Shotter believes is (deliberately?) misleading, as it implies that he suddenly exploded out of nowhere onto the political scene. We know that Sejanus already had a political role before then – in AD14 he accompanied Tiberius’, Drusus, on his mission to put down a mutiny among the Pannonian legions.

How did Sejanus acquire such influence over Tiberius?

1.       Sejanus came across as loyal, efficient, hard-working and independent – all qualities which Tiberius highly prized – without being sycophantic, which Tiberius detested.

2.       Tiberius felt comfortable in the company of soldiers as he did not rust many people. Due to the fact that he became emperor relatively late in life, he felt increasingly isolated during his reign as his friends and relatives died – this left him increasingly reliant on someone in whom he did not feel confident.

3.       Sejanus made a very careful study of Tiberius’ character and played on his insecurities.

4.       By AD23, Tiberius was approving statues of Sejanus in Rome and calls him socius laborum “partner of my labours”.


What were Sejanus’ aims?

1.       To prevent any reconciliation between Tiberius and Agrippina (Germanicus’ widow). Remember that Agrippina believed Tiberius had poisoned Germanicus.

2.       To isolate Tiberius and control access to him e.g. when Tiberius retires to Capri.

3.       To undermine those who might have helped Tiberius or given him good advice.

4.       To dominate Tiberius by making him reliant on him for the efficient administration of the Empire.

5.       To become Tiberius’ successor, which would require marriage into the imperial family.

Sejanus’ actions

1.       Sejanus persuaded Tiberius that the cohorts of the Praetorian Guard should be brought together into a single camp on the eastern side of Rome – to increase the sense of group cohesion and enable more efficient deployment and transmission of orders. In practice, this was to increase Sejanus’ own power as commander of a large fighting force within Rome itself. Wiedemann argues that it actually made sound sense to concentrate the Praetorian Guard in a single camp.

2.       Sejanus seduced Drusus the Younger’s wife, Livilla (sister of Claudius) and together they planned and executed Drusus’ murder (Tiberius was unaware of this until AD30). Sejanus hoped that he would be able to marry the widowed Livilla and thus gain control over Tiberius’ only remaining direct descendent, his grandson Tiberius Gemellus (particularly if Tiberius died whilst Gemellus was still a minor). However Tiberius refused permission for Sejanus to marry Livilla (because of his equestrian status).

3.       Sejanus deliberately set out to drive a wedge between Tiberius and Agrippina. Tiberius’ aims in terms of the succession had been that Drusus should be the guardian of Germanicus’ elder sons, Nero and Drusus, in order to marginalise Agrippina and her circle. Sejanus exploited Tiberius’ suspicion of Agrippina by engineering law cases against particular friends of Agrippina whom Tiberius was unlikely to feel any sympathy for; he manipulated these cases to ensure it appeared to Agrippina that it was Tiberius himself, not Sejanus, who was orchestrating the attacks on her and her friends – e.g. the attack in AD24 on Gaius Silius and his wife Sosia Galla. In AD26, an attack was launched on Agrippina’s cousin, Claudia Pulchra. In his regular briefings to Tiberius, he built up the concept of a party or faction centred on Agrippina. Sejanus also managed to convince both Agrippina and Tiberius that the other one was trying to poison them.

4.       Sejanus may have persuaded or driven Tiberius into his decision to retire from public life in Rome in AD26 (when he was 67) and spent the rest of his reign on Carpi or in the near Naples area. According to Tacitus, it was an incident at one particular trial, the trial of Votienus Montanus that pushed Tiberius into retirement. He was forced to listen to a witness (probably hand-picked and instructed by Sejanus) repeating a strong of very unpleasant remarks about Tiberius that had supposedly been made by the accused, including allegations about his sexual perversions.

5.       Sejanus intended that Tiberius should become dependent on him for information, so he became the censor of news to and from Capri. Also, with Tiberius away from Rome, it would be easier for Sejanus to undermine Agrippina, her friends and family.

6.       On the way back to Carpi, by chance, Sejanus was able to reinforce Tiberius’ trust and reliance on him when he saved his life during a rock fall at a cave near Sperlonga, near Naples, where Tiberius was picnicking. It was in his interests to keep him alive as it was necessary for Tiberius to name his successor.

7.       Once Tiberius was on Capri, Sejanus targeted Nero, the eldest son of Germanicus and Agrippina, for harassment and intimidation. He exploited the jealousy and suspicion that existed between Nero and his brother Drusus. Sejanus continued to pose as Agrippina’s friend and this increased her insecurity. In fact, Sejanus so successfully appeared as Agrippina’s friend that after Sejanus’ fall, Tiberius found it very difficult to accept that Agrippina and her family were not associated with Sejanus.

8.       Livia acted as a restraint on Sejanus’ behaviour while he still lived, but her death in AD29 removed this check on him. Soon after her death, Agrippina, Nero, Drusus and a number of their supporters were imprisoned; Nero committed suicide in prison in AD30 (starves to death). 

9.       In AD30-31, Sejanus tried to build further support for himself amongst the plebs of Rome and among the armies. He made approaches to the commanders of the armies of Upper and Lower Germany, seeking the promise of support in the event of Tiberius’ eventual death.

The Fall of Sejanus

N.B: Tacitus’ account of the fall of Sejanus in AD30-31 is now lost. Juvenal (of all people) is actually a major source for the fall of Sejanus, as her refers to it in his Tenth Satire.

Tiberius was warned about Sejanus in AD30 (apparently by Antonia, Tiberius’ sister in law and Claudius’ mother), but he didn’t take public action until October AD31 (needs to plan as he is not in Rome, Sejanus could have assassinated him). In AD31, Tiberius appointed himself and Sejanus as joint consuls. Tiberius rarely held the consulship himself throughout his reign (as hogging the consulship would have gone against his principle of trying to encourage senatorial independence) and this was only his fifth consulship. Previously, he had shared the consulship with his tow sons and heirs, Drusus and Germanicus, so his shared consulship with Sejanus implied that he was planning further promotions for Sejanus – Tribunician power? Permission to marry Livilla and therefore become part of the Imperial family (thus designating him as his heir?). However, Tiberius resigned his own consulship in May (to make Sejanus feel insecure?).

Tiberius took very few people into his confidence about his plans to cause Sejanus’ downfall – apart from Sertorius Macro (the deputy prefect of the Praetorian Guard, who was to become Sejanus’ replacement) and Memmius Regulus, Tiberius’ replacement as consul.

Wiedemann describes the execution of Sejanus on 18th October AD31 as “one of the most carefully stage-managed events in Roman history”. At the senate meeting, Macro replaced the guard of Praetorians with soldiers of the night watch (vigils), then handed over a letter from Tiberius to the senate regarding Sejanus – it was carefully worded so as to leave Sejanus in the expectation of promotion until the very last moment. After being denounced, Sejanus was led off to execution and the Roman people destroyed his statues.

Tiberius is said to have stated in his own autobiography (now lost) that he destroyed Sejanus because of his plots against the children of Germanicus. This claim might actually be true as shown by the fact in AD30, apparently acting on Antonina’s advice, Tiberius had Caligula and his sisters (Drusilla, Livilla and Agrippina) brought to Capri – perhaps in order to offer them improved protection and get them away from Rome and Sejanus.


The Aftermath of Sejanus’ Death

The death of Sejanus was followed by a witch hunt against his supporters – unfair, in the view of the fact that Tiberius’ trust in Sejanus and his mandate to him would have encouraged people to try and keep in with Sejanus. Sejanus’ estranged wife, Apicata, who committed suicide, before she died, told the full story of Sejanus’ relationship with Livilla and their murder of Drusus. Junius Blaesus, Sejanus’ uncle, also committed suicide.

Drusus (Germanicus’ second son) died in AD33, provoking an attack from Tiberius about the damage that Drusus had done to Rome and his family. Assuming that Tiberius now knew the role that Drusus had played in helping Sejanus to bring down his brother Nero, this attack was actually justified. Tiberius could legitimately have regarded Drusus as an accomplice of Sejanus.

Agrippina died on 18th October AD33, exactly two years to the day after Sejanus’ execution. This coincidence was not lost of Tiberius, who saw Agrippina and Sejanus as conspirators bent on his destruction.

In the case of Asinius Gallus (senator who had married Vipsania and used to wind up Tiberius during the senate meetings), Tiberius felt (not unreasonably?) that Gallus had been trying to undermine him for a long time, through his behaviour in the senate. Agrippina had hoped to marry Gallus, although Tiberius refused permission (partly because this might encourage Gallus himself to mount a claim on princeps). Tiberius was convinced that Gallus has been in cahoots with Sejanus.

The Legacy of Sejanus

1.       In order to further his own ambitions of imperial power, Sejanus brought about the near destruction of the imperial family, leaving very few viable candidates to be next emperor (Caligula, Tiberius Gemellus and of course, “old uncle Claudius”).

2.       The sycophancy of the senators increased further.

3.       Tiberius refused to ever enter Rome again.

4.       Fear and suspicion among the nobility – would have felt that they did the right thing supporting Sejanus but then saw what happened to the others.

5.       Macro, the new Praetorian Prefect, was even more cruel, depraved and power hungry than Sejanus. Tiberius removed Sejanus but allowed his even worse replacement to have enormous power too. He did not learn from his mistakes.

6.       The whole Sejanus episode highlighted the sensitivity of the relationship between princeps, army and Praetorian Guard. Few emperors were prepared to risk antagonising the Praetorian Prefect, so much so that Vespasian later experimented with giving this post to members of his own family.


Tiberius and the Treason Trials

The Treason law before Tiberius’ Principate

·       In the late Republic, there was a law against committing actions which “diminished the majesty of the Roman senate and people”.

·       Augustus revised this law to produce the Lex Julia da maiestate (Lex = law, Julia as Augustus was a member of the Julian clan, maiestas means treason in Latin).

·       Augustus extended the law to include treasonable words, written or spoken, as well as actions.

·       Under Augustus, the law increasingly became restricted to actions or words which were alleged to have damaged the princeps or his family.

·       Augustus extended the remit of the senate, giving it a judicial function to hear cases against its own members.

Weaknesses of the Treason Law in Tiberius’ Principate

·       Insufficient/vague definition of treason – any action or words which “diminished the majesty of the Roman state or people”.

·       Evidence based on hearsay – reports of conversations etc.

·       No public prosecutor/state prosecution service.

·       The Romans had no public prosecutor. Instead it fell to individual prosecutors/informers (delatores) – eager to gain one quarter of the property of the accused if they were convicted (an incentive to prosecute the wealthiest citizens). In AD25, there as a proposal that the informers should not receive their award if the accused person committed suicide before the trial finished. Tiberius stopped this measure before it was passed. Insisting that the law remain. Tacitus saw this as support for the informers but it could also signify respect for the law.

·       Intimidation of witnesses.

·       Treason cases were tried by senators keen to ingratiate themselves with Tiberius.

·       Tiberius himself insisted on sitting in on treason cases, whether they were heard in the senate or in the permanent court (quaestio de maiestate) which was presided over by a praetor. His presence intimidated members of the court.

·       Tiberius’ ambivalent attitude and his insistence of remaining impartial and not intervening in the senate’s decisions made it difficult for the senate to gauge what he wanted, as he failed to give clear guidance on what outcome he wanted for each case (awkward when the cases related to him himself).

·       Tiberius introduced a 9 day cooling off period between sentencing and execution – in theory to give time for sentences to be reconsidered – but this made no difference because he never changed his judgements during this period, and the senate did not wish to risk angering him by changing their judgement.

·       The use of the reason law damaged Tiberius’ own attempts to present himself as “just another senator”, as these cases – which related to insults made against him or his family – served to emphasise the fact that he was really on a higher level than the other senators.

·       Successful treason convictions often led to sycophantic behaviour on the part of senators (proposing thanksgiving sacrifices to gods etc.) which served to further undermine their independence and integrity.


In the reign of Tiberius, there were eighty six maiestas cases in the “reign of terror” but at least thirty of the charged were acquitted. There were eighteen executions but the majority of these were for conspiracies not slander of Tiberius. Tiberius also quashed many convictions and reduced the severity of others.

The senate must bear some responsibility for the reason trials and many occurred whilst Sejanus was in charge of Rome.  It does appear that there were more prosecutions after Sejanus’ death, when the senate took the opportunity to rid the state of his supporters. Towards the end of his reign, Tiberius convicted a few people 0 but his experience of Sejanus had led him to become insecure and fearful. One of the people convicted was Sextus Paconianus, who was charged with writing satires against Tiberius.

Suetonius’ summary of treason charges (Life of Tiberius, 58)

“One man was accused of decapitating an image of Augustus with a view to substituting another head; his case was tried before the senate and, finding a conflict of evidence, Tiberius had the witnesses examined under torture. The offender was convicted, which provided a precedent for far-fetched accusations: people could now be executed for beating a slave, or changing their own clothes close to an image of Augustus, or carrying a ring or coin, bearing Augustus’ head into a lavatory or brothel; or for criticising anything Augustus had ever said or done. The climax came when a man died merely for letting an honour be voted on him by his native town council on the same day the honours had been voted to Augustus.”

Tiberius and the Senate

The Treason Trials profoundly affected the most important political body in Rome – the Senate. It instilled a sense of fear and resentment in the Senators. However it also could be used as a tool to rid am ambitious senator of a political rival, by accusing them of treason.

The Treason Trials also affected Tiberius’ relationship with the senate in another way. Rather than hardening the opposition to Tiberius, it only increased the sycophancy that Tiberius hated so much.