How did Emperor Septimius Severus change the Roman Empire?

Bust of Septimius

Septimius Severus (145-211 AD), is not one of the better known Roman Emperors, but he was one of the most important in the history of the Roman Empire. He was a very capable man, a successful administrator, and general. He reformed the government of Rome and won many victories on the battlefield. Under Severus, the Roman Empire reached its greatest extent and he founded a dynasty. Despite these real achievements, many regard Septimius Severus as fatally undermining Rome.

Septimus Severus was a successful emperor and achieved short term goal, but ultimately his reign marked an important stage in Rome's decline. Severus created a ‘military monarchy’, marginalized the Senate and his expansion of the army weakened the economy. He was at least partially responsible for the so-called ‘Crisis of the Third Century’ when the Roman Empire almost collapsed.

Life and Reign of Septimius Severus

Ruins of the defensive works built by Septimius in North Africa

Septimius Severus was born in, Leptis Magna, Tripolitania (now in Libya). He was the son of a knight or a member of the equestrian order and he was of Punic or Carthaginian descent. Severus first language was Punic, and he remained proud of his Carthaginian heritage.[1] He entered the Senate about 173 AD, he was very young to become a senator but his way was eased because so many members of the elite had died in a great plague the previous year.

Severus was a senator at a very difficult time as Commodus the unstable son of Marcus Aurelius was embarking on a reign of terror in Rome and he had many Roman aristocrats murdered. The African senator managed to stay alive and even to flourish during these dark days and was made governor of a key province and the command of three legions. When the mad Emperor Commodus was assassinated there was turmoil in Rome. His successor was murdered by the Praetorian Guards and the next Emperor (Marcus Didius Julianus) purchased the Imperial diadem or crown. Severus on the Danube was the commander of the largest army in the Empire.[2] He ordered his army to march on Rome and he entered the city without resistance and he became Emperor. However, he was not unchallenged.

Severus had to agree to recognize Clodius Albinus as the de-factor ruler of the western part of the Empire. While in the East, Gaius Pescennius Niger held several provinces. After a series of civil wars, Septimius Severus emerged victoriously and he became the unchallenged ruler of the Roman World. First, he defeated Niger in the east before he vanquished Clodius Albinus in a close fought battle. After this, he was the absolute ruler of the Roman Empire. Severus was the first African native to be Emperor of Rome. He used his power to reform the system and made sweeping changes to the army. For example, he replaced the Praetorian Guard with a large Imperial bodyguard, that was drawn from the legions. In 197 AD Septimius Severus turned to Rome’s old enemy Parthia and he invaded the large province of Mesopotamia (now in Iraq). He was successful and even attacked the Parthian capital, Ctesiphon and he permanently annexed Mesopotamia for the Empire.[3]

In late 2001 he traveled to his native Africa and campaigned against the Garamantes, these were an African people who had developed a sophisticated kingdom in what is now Libya. Severus army overwhelmed the Garamantes and even occupied their capital. He also campaigned in Numidia and defeated a local confederation of tribes and added more territory to the Empire. From 202 to 208 AD he overhauled the Imperial administration and government.[4]

A provincial himself he helped many provincials and those from poor backgrounds to rise in the Roman government. Severus devoted himself to the reform of the law, something which had not been done in over a century. As he grew older he raised his sons Geta and Caracalla to positions of power. They were both elevated to the status of Caesars and the co-rulers of the Empire. Severus was keen to secure the support of the people and he made himself popular with his lavish donations and by staging games. However, the elite hated him, and he reciprocated this, and he had poor relations with the aristocracy in Italy.

In 208, Severus journeyed to Britain with a larger army to conquer the Picts (in modern Scotland). Severus campaigned successfully against the Picts and occupied much of Scotland, the first Roman to do so for over a century. He extended the Roman frontier and added southern Scotland to the Empire. Severus succumbed to the disease at Eboracum, now the city of York. His sons succeeded him as co-Emperors. Apart from the rule of the usurper Macrinus (218 AD), Severus’s descendants remained in power until 235 and the start of the Third Century Crisis, when the Empire almost imploded under the pressure of economic problems, military mutinies, and barbarian invasions.

Septimius and the Provinces

Septimius was a very active campaigner and unlike many of his predecessors was very knowledgeable about the provinces. He was very loyal to his native Africa and did much to help that region of the Empire which despite its wealth had been neglected.[5] Severus helped to pay for a lavish building program that greatly benefited the cities of Africa. His patronage brought a great deal of prosperity to the African provinces. His defeat of the Garamantes was intended to secure Rome’s African frontier as was his campaign in Numidia. Prior to these campaigns the Garamantes and others would regularly raid the African provinces. After Septimius campaign, there was an era of peace and stability in Africa.

Septimius expanded the frontier and established a series of limes (defensive lines) that protected the Romans in Africa for many generations. In Britain, Severus reoccupied territory that had been abandoned and he rebuilt the Antonine Wall.[6] This protected the Roman province of Britannia from Pict attacks for many years. Moreover, he divided the British province in two. This was to make the administration of the provinces more efficient and this was a success. Successive Roman Emperors maintained the division of Britannia into two. In the east, Severus won several significant military victories and he added Mesopotamia (northern Iraq) to the Empire.

After his reign, the eastern frontier was pacified for several years. This was partly because of the growing weakness of Parthia but it was also because Severus' acquisition of Mesopotamia meant that the Romans were in a very strong strategic position in the east. The victories secured by the first African Emperor helped to secure the eastern frontier for some fifty years. However, there are those who argue that in the longer term the African Emperor’s conquest of Mesopotamia weakened Rome in the east, especially after the rise of the Sasanian Empire.[7]

Severus and the law

Ruins of the Arch in Rome built by Septimius Severus

Severus was very concerned with the administration of justice. The Italian courts were removed from senatorial jurisdiction and put under the control of the praetorian prefect. Severus hoped that this would reduce corruption in the administration of justice. He also removed the right of Senators to sit in courts and act as judges. This was part of his campaign against Senatorial privilege and also another part of his effort to improve the quality of justice.

In 205 AD, Severus executed the praetorian prefect and replaced him with the great jurist Papinian. Under him, the law was codified and reformed. Severus also consulted with the renowned jurist Ulpian and the Roman law code was updated and rationalized. Severus oversaw perhaps the most extensive reform of the laws of the Empire since Augustus.[8]

Severus and the Army

Severus needed the support of the army to stay in power. He was after all not the legitimate Emperor and the support of the legions had allowed him to seize the Imperial diadem. The African was very conscious of the fact that he was technically a usurper and he invented spurious claims that he was the descendant of Emperor Nerva. He gave the army a leading role in the state and expanded the number of legions.[9] The first African Emperor is often stated to have made the army the most important institution in the state and in fact the only one that mattered in the Empire.

The army attained a level of unprecedented level of influence in the Empire under Severus, which it never lost. Moreover, the size of the army was a considerable burden on the economy and weakened it in the longer term. The elevation of the military's influence lead to instability in the decades following Severus death. The founder of the Severin dynasty gave the army a pay increase, according to the one source he ‘gave his soldiers sums of money such as no emperor had ever given before.’[10] To fund these increases, Severus was forced to debase the Imperial currency.

It has often been claimed that because he debased the currency, he ultimately caused the catastrophic inflation of the Third Century. However, Severus had a full treasury and his administration of the Imperial finances was excellent. It cannot be denied that he established a precedent for Emperors to debase the currency to pay the soldiers and this was to have disastrous financial and economic consequences for the Empire, especially in the Third Century. Severus ended a long tradition by allowing soldiers to marry. This, it is claimed led to a decline in standards of discipline in the army.

Later commentators deplored Severus decision to allow soldiers to marry and believed that it diminished the army as a fighting force.[11] Married soldiers were reluctant to be transferred to other provinces and they would often mutiny if ordered to do so. Severus was very conscious of the threat of rebellion and to limit the risk of a powerful military rival, he reduced the number of legions under his general's control. This did not limit military rebellions and may even have reduced the effectiveness of the legions. Severus military policies at once placed a great strain on the Roman economy and created a military that was conscious of its power. This was to have terrible consequences in the Third Century when the legions could make and unmake Emperors at their will.[12]

Severus and the Senate

Severus raised the status and influence of the army. However, he ignored and even persecuted members of the old senatorial order. Septimius was aware that he had seized power and was not a constitutional monarch. He knew that the Senate disliked him and saw him as a usurper.[13] He marginalized both the Senate and the Italian aristocracy that had traditionally played an important role in the government of the Empire. Severus ended this tradition. He would often appoint commoners and non-Italians to high offices and governorships. This infuriated the Senatorial class. However, Severus did not tolerate any opposition and he either executed or exiled several Senators.

The reign of the first African Emperor was to see a rapid decline in the prestige and the influence of the Senate. Real power no loner lay with the Senate but with the bureaucracy and the army. Severus dismantled the long-established system that was established by Augustus where the Emperor would share power with the Senate and the Italian aristocracy. Instead, Septimius Severus reign was one that has been characterized as a ‘military monarchy.’[14] Severus legitimacy did not come from any political institution but from the army.

In subsequent periods, any general with the support of the legions could claim the Imperial throne leading to endemic instability. The development of a ‘military monarchy’ was one of the main reasons for the so-called ‘Crisis of the Third Century.’[15]


Septimius Severus was in many ways a successful Emperor and could even lay claim to the title of a great Emperor. He was a successful general and administrator and strengthened and expanded the Empire and established a dynasty. Severus was also a great legal and administrative reformer. However, during his reign, he expanded the army so much that ultimately it undermined the financial health of the Roman economy. The first African born Emperor also established a de-facto military monarchy and he gave the army unprecedented power and privileges and this contributed to the period of near-anarchy known as the Third Century Crisis, during which the Empire almost collapsed.

Suggested Readings


  1. Birley, Anthony R., Septimius Severus: The African Emperor (London: Routledge, 1999), p. 15
  2. Birley, p. 56
  3. Grant, Michael. The Severans: The Changed Roman Empire (Routledge, London, 1996), p. 17
  4. Birley, p. 17
  5. Birley, p. 114
  6. Grant, p. 17
  7. Grant, p. 19
  8. Birley, p 99
  9. Campbell, Brian. The Roman Army, 31 BC-AD 337: A Sourcebook (London, Longman, 1997), p 119
  10. Life of Septimius Severus: Historia Augusta, x
  11. Campbell, p. 120
  12. Campbell, p. 137
  13. Life of Septimius Severus, x
  14. Hekster, Oliver, Rome and its Empire, AD 193–284 (Edinburgh, Archer Press, 2008), p. 201
  15. Hekster, p. 232


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