The Praetorian Guard (praetorium), organised by Augustus in BC 2 for his own protection, was at first divided, three cohorts being stationed close to Rome, and six more at various imperial residences in Italy. Tiberius collected all the nine cohorts in one barrack at Rome. Each praetorian cohort consisted of 800 or 1,000 men, partly horse and partly foot (miliariae equitatae) divided into centuries and commanded by centurions. They were recruited entirely from Italians, and had numerous privileges apart from the special favour of the emperor, whom they protected. They received double pay - 720 denarii a year - while the legionary soldiers received only 225, and they served only for sixteen years certain, while the legionaries were bound for twenty. The praetorians were commanded commanded at first by two praefecti praetorio, and later by the praefectus praetorii.
At a later period they became the masters of the empire. Their insolence became proverbial. It reached a climax when they murdered Pertinax and sold the Empire by auction to Didius Julianus. Septimius Severus took vengeance upon them, dissolved the existing body, and replaced it by a guard composed of soldiers of tried valor chosen from the legions.
The Emperor was guarded by a band called the Praetorian, because, before the time of Augustus, it had been attached to the service of the Praetors. The men were chosen from the bravest of the legions, and having the person of the emperor always in their hands, had full power over his life, so that it was in them that the whole overgrown influence of the army was concentrated.
The Praetorian Guard was formed by the emperor Augustus to help prevent assassins from reaching the emperor and murdering him as Brutus and his companions had murdered Julius Caesar. It was called by that name in imitation of the Praetoria Cohors, or select troop, which attended the person of the praetor or general of the Roman army. This cohort is said to have been first formed by Scipio Africanus out of the bravest troops, whom he exempted from all their duties except guarding his person.
Emperor Augustus made the praetorians a standing force after the battle of Actium in 31 BC. He divided them into nine cohorts (groups) of 500 soldiers each, just as with the regular legions. Augustus, in accordance with his general policy of avoiding the appearance of despotism, stationed only three of these cohorts in the capital, and dispersed the remainder in the adjacent towns of Italy. Before 2 BC each individual cohort was lead by a tribune of equestrian rank. Afterwards, Augustus created two posts for overall command of the guard, the Praetorian Prefects.
The primary role of the Praetorians was to act as a bodyguard to the emperor and serve as a police force in the city. However, they did take to the battlefield when the need arose. Members of the guard received much higher pay than other soldiers. The scorpian appears as a symbol on much of the Praetorian equipment, possibly due to the fact that the birthsign of emperor Tiberius was scorpio. In the city, they wore no armor and carried no shield. They wore a plain tunic and carried a sword. On the battlefield they were outfitted with the same equipment as the normal legions.
The introduction of standing armies at the time of Augustus, already long prepared, naturally followed a dominion acquired by war; and became, indeed, necessary to guard the frontiers and preserve the newly-made conquests. The establishment of the guards and militia of the city (cohortes pratoriana and cohortes urbarue) were measures equally necessary for the security of the capital and the throne. The creation of two praetorian praefects, however, instead of one, diminished for the present the great importance of that office.
The "praetorium" was a council of war, the officers who met in the general's tent. The Pratorium was originally the headquarters of a Roman camp, but in the provinces the name became attached to the governor's official residence. In order to provide residences for their provincial governors, the Romans were accustomed to seize and appropriate the palaces which were formerly the homes of the princes or kings in conquered countries. Such a residence might sometimes be in a royal palace, as was probably the case in Caesarea, where the procurator used Herod's palace.
The "praetorium" was a council of judgment, the emperor's court of appeal in which he was assisted by his legal assessors. Over this court there presided the emperor or his delegate, the prefect of the pratonan guard, and associated with him were twenty assessors selected from the senators. Tho Pratorium is the whole body of persons connected with the sitting in judgmont, tho supreme Imperial Court, the Prefect or both Prefects of tho Praetorian Guard, representing the emperor in his capacity as the fountain of justice, together with the assessors and high officers of the court.
The garrison of Rome consisted of the pretorian guard, nine, later ten - cohortes praetoriae; three, later four, cohortes urbanae; and seven cohortes vigilum, the police and fire department organized in 6 AD. All these cohorts had an individual strength of 1,000 men. The soldiers of the pretorian cohorts received 720 denarii a year, and served 16 years; those of the urban cohorts received probably 360 denarii and served 20 years.
Under the Emperor Tiberius Rome soon experienced to her cost the powerful ascendency which L. AElius Sejanus, the prsefect of the praetorian guard, had acquired over the mind of Tiberius, whose unlimited confidence he possessed the more, as he enjoyed it without a rival. Tiberius gradually gave much of his power to Sejanus, the commander of the Praetorian Guard. Sejanus used his position to murder his enemies, accusing them of plotting to assassinate the emperor and other acts of treason. Tiberius, under pretence of introducing a stricter discipline among them, assembled them all at the great Praetorian Camp [the Castra Praetoria] on the Viminal Hill in Rome. In AD 23 this huge and strongly fortified camp was established in the eastern suburbs of the city by their notorious commander, Lucius Aelius Sejanus.
The concentration of the pretorian cohorts in a single fortified camp in Rome which increased their esprit du corps and confidence in their own strength. The eight years of his authority were rendered terrible not only by the cantonment of his troops in barracks near the city (castra pratoriana), but (having first persuaded Tiberius to quit Rome for ever, that he might more securely play the tyrant in the isle of Capreae) by his endeavoring to open a way for himself to the throne by villanies and crimes without number. The fall of Sejanus was attended with great carnage in 31 AD.
In 37 AD Caius Caesar Caligula ascended the throne. Caligula, who succeeded [and may have assasinated] Tiberius, paid the Praetorian Guard one thousand sesterces each which was bequeathed to them in Tiberius' will, but Cassius Dio claims that a generous amount was given to them out of the pocket of Gaius himself probably for the purpose of maintaining their loyalty. Caligula became dangerous and unstable. After a career of nearly four years, Caligula was assassinated by Cassius Chaerea and Cornelius Sabinus, two officers of the Praetorian Guard, because he had made a mockery of the military and alienated the leaders of the Guard.
The Praetorians soon became the most powerful body in the state, and like the janissaries at Constantinople, frequently deposed and elevated emperors according to their pleasure. After the Praetorian Guard murdered Caligula, they made a significant contribution to the imperial appointment of Tiberius Claudius Caesar at the age of fifty in 41 AD. Claudius was the first emperor raised to the throne by the Praetorian Guard; a favor which he rewarded by granting them a donative, purchasing the submission of the soldiers with money. Even the most powerful of the emperors were obliged to court their favor; and they always obtained a liberal donation upon the accession of each emperor.
The chief aim of the second wife of Claudius, Agrippina, was to procure the succession for Domitius Nero, who had been adopted by Claudius. This she hoped to effect, by poisoning Claudius, having already gained Burrhus, by making him sole praefect of the praetorian guard. Nero Claudius Caesar, supported by Agrippina and the praetorian guard, succeeded Claudius at the ago of seventeen. The last years of Nero were marked by a striking and undoubted insanity. The praetorian guard, instigated thereto by Nymphidius, broke out into rebellion in Rome itself and soon followed the death of Nero, June 11, 68 AD.
The right of the senate to name, or at least to confirm, the successors to the throne, was still indeed acknowledged; but as the armies had found out that they could create emperors, the power of the senate dwindled ir to an empty ceremony. Servius Sulpicius Galba, having been already proclaimed emperor by the legions in Spain, and acknowledged by the senate June 11, 68 AD, gained possession of Rome without striking a blow. Galba, however, having given offence both to the praetorian guard and the German legions, was dethroned by the guards on Jan. 15, 69, at the instigation of his former friend Otho.
The Praetorian Guard's number was increased by Vitellius to sixteen cohorts, or 16,000 men. Vitellius transferred many experienced soldiers into the Guard in AD 69 but they were generally recruited from among the young sons of the landed Italian gentry. By the reign of Domitian the praetorian guard had been increased to ten cohorts, each structured like the primary cohort of a legion (i.e. containing five double-strength centuries). Flavius Vespasian soon ascended the throne, and became thereby the founder of a dynasty which gave six emperors to Rome. The state, almost ruined by profusion, civil war, and successive revolutions, found in Vespasian a monarch well suited to its unhappy condition.
By means of adoption the Roman empire had been blessed, during eighty years, with a succession of rulers such as had not often fell to the lot of any kingdom. But in the son of Marcus Aurelius, Commodus [who reigned from March 17, 180-Dec. 31, 192] his nineteenth to his thirty-first year, there ascended the throne a monster of cruelty, insolence and lewdness. At last he was killed at the instigation of his concubine Marcia, Laetus the praefect of the praetorian guard, and Electus. During nearly a century after the death of Commodus, son of Aurelius, and last of the Antonines, the Empire was in the hands of the army, which would brook no commander save at their own pleasure. They raised Emperors, and killed them at their pleasure, and were the real masters of Rome.
The insolence of the praetorian guard had risen very high during tho reign of Commodus; but it had never, even in the time of the Antonines, been entirely suppressed. It was only by large donatives that their consent could be purchased, their caprice satisfied, and their goodhumor maintained; especially at every new adoption. One of the greatest reproaches to the age of the Antonines is, that those great princes, who seem to have had the means so much in their power, did not free themselves from so annoying a dependence.
In A.D. 193 P. Helvius Pertinax, aged sixty-seven, praefect of the city, was raised to the throne by the murderers of Commodus; and that he was acknowledged, first by the guards, and afterwards by the senate. But the reform which he was obliged to make at the beginning of his reign in the finances, rendered him so odious to the soldiers and courtiers, that a revolt of tho first, excited by Laetus, cost him his life before he had reigned quite three months. The Praetorians assasinated the emperor Pertinax, who had ruled for eighty-seven days after the assasiantion of Commodus. This was the first commencement of that dreadful military despotism which forms the ruling character of this period ; and to none did it become so terrible as to those who wished to make it the main support of their absolute power.
Thus ensued a most disgraceful business and one unworthy of Rome. For, just as if it had been in some market or auction-room, both the city and its entire empire were auctioned off to Didius Julianus, a wealthy member of the Senate. When, upon tho death of Pertinax, the rich and profligate M. Didius Julianus, aged fifty-seven, had outbid, to the great scandal of the people, all his competitors for the empire, and purchased it of the praetorian guard, an insurrection of the legions, who were better able to create emperors, very naturally followed. The army of Illyria proclaimed their general Septimius Severus, who was the first to got possession of Rome.
Didius Julianus ruled only sixty-six days, and upon his assasination he was replaced by Septimius Severus (A.D. 193-211). After the execution of Didius Julianus, Septimius Severus was acknowledged by the senate. Septimius Severus gained several victories over the Germans, went to Britain, and penetrated further into Scotland than any Roman had yet ventured, after which he built a second wall across the island, and was returning southwards, when he was taken ill, and died at York.
Septimius Severus, who succeeded Didius Julianus, disbanded the Praetorian Guard as unreliable and seditious, on account of the part they had taken in the death of Pertinax, and banished from the city. The emperors, however, could not dispense with guards, and accordingly the Praetorians were restored on a new model by Severus, and increased to four times their ancient number. Until the reign of Septimius Severus, only soldiers recruited in Italy could serve in the guard. Instead of being levied in Italy, Macedonia, Noricum, or Spain, as formerly, the best soldiers were now drafted from all the legions on the frontiers; so that the praetorian cohorts now formed the bravest troops of the empire. Severus possessed most of the virtues of a soldier; but the insatiable avarice of his minister, Plautianus, the formidable captain of the praetorian guard, robbed the empire even of those advantages which may bo enjoyed under a military government.
The prefect or captain of the praetorian guard became, from the time of Septimius Severus, the most important officer in the state. Besides the command of the guards, the finances were also under his control, together with an extensive criminal jurisdiction-a natural consequence of the continually increasing despotism.
The soldiers allowed the succession to remain in his family, but Caracalla, his son, proved cruel and wicked. Heliogabalus, his grandson, went beyond all the rest of the emperors in the wildness of his profligacy; and though Alexander Severus, the last of the family, was a youth of promise, the avarice of his mother, Julia Samias, so irritated the soldiers, that they killed them both. The names of the persons whom they subsequently elevated are, for the most part, not worth recording. Instead of protecting the emperor from assassination, many times the Praetorian Guard were the very ones to murder an emperor, especially during the political chaos of the Third Century.
After the murder of Severus Alexander in 235, the empire entered a period of almost continuous civil war and campaigns against barbarian attacks which lasted until Aurelian restored order between 273 and 275. Some emperors held the throne for a few years, some only for a few days, and often the Praetorian Guard would put one of its favorites on the throne only to become dissatisfied with him later and choose another candidate. This pattern of murder and military rule by the Guard continued until the reign of Diocletian.
The Guard's effective destruction came at the battle of Milvian Bridge in AD 312. Constantine finally disbanded the Guard for good, deeming it more a dangerous nuisance than imperial protection. In its place, he instituted the SCHOLAE PALATINAE, or palace guard. They were organized differently and better regulated than the Praetorian Guard.
The Praetorian Guard has become a byword for any military force which is used to prop up a ruthless regime.