The Praetorian Guard was formed by Augustus. When Octavian Caesar became Augustus and the first Emperorof Rome in 27 B.C. he realized that he must have some form of protection. While important figures in Romanpolitics did have a bodyguard protecting them, Augustus thought he deserved more, so he chose 9 cohorts of veteran soldiers and exemplary youths and called them the ‘Cohors Preatoria’ or ‘Select Cohorts’. BecauseAugustus did not want to give off an air of despotism he kept only three cohorts in Rome’s limits and forbade them for wearing armor or weapons. The three cohorts stationed in Rome were called the ‘Cohors Togata’, because they wore togas instead of armor. The togas the Praetorians wore in Rome looked like those of the ‘lictors’ who protected the Roman Consul, but unlike lictors the Praetorians carried a sword in the folds of their togas. From 27 B.C. until 2 B.C. there were no major changes to the Praetorian Guard in either size or structure, and then in 2 B.C. Augustus created the office of ‘Praefectus Praetorio’ or ‘Praetorian Prefect’ to lead the guard. Until this point each cohort was lead individually by a tribune, now the guard had a more solid command structure with two men of high rank being in command. The last major happening in the guard duringAugustus’ time was in 5 AD when the number of men in each cohort was increased in size from 500 men to 1,000 men.
The famous meddling in politics started during the time of Tiberius. After Augustus died in 14 AD Tiberiusascended to the throne he started the practice of giving the guard a ‘Donativum’ or ‘Imperial Gift’ upon ascension. It was also during Tiberius’ reign that the guard received their most famous prefect: Lucius Aelius Sejanus. Under Sejanus the guard began enjoying power over the Emperor. In 23 AD Sejanus ‘convinced’Tiberius to move the Praetorian barracks from the Italian countryside to Rome itself, this new barracks was named ‘Castra Preatoria’ or ‘Camp of the Praetorians’, in addition one extra cohort was added to the three already in Rome. This move was the start of a dangerous power game between the Praetorians and Tiberiusand this became manifest several times ending in Sejanus’ death at Tiberius’ orders. From that point things were rather quiet, but the Praetorians would take a new step in power in the reign of Tiberius’ successorCaligula.
During the time of Caligula the Praetorians took a new step in political power. In 41 AD a coalition of Senatorsand Praetorians assassinated the Emperor Caligula because he had insulted the Roman military and institutions; they also thought him mentally unstable. In Caligula’s place they elevated his uncle Claudius to the throne, when the Senate opposed the elevation the Praetorians threatened death and mayhem. To everyone’s surpriseClaudius turned out to be a good Emperor and in 47 AD he increased the number of cohorts to twelve as thanks to the Guard. From then on the Praetorian Guard became the most powerful force in Rome; Emperors did not become Emperors or stay in their position unless they bribed the Praetorians first. In 69 AD Nero (ThePraetorians had deserted him by then) and the Roman Empire suffered its first major crises as the Julio-Claudian dynasty was toppled and 4 successive generals became Emperor in one year, usually by bribing thePraetorian Guard first. One of these general-emperors, Vitellius, increased the Praetorian Guard’s size from twelve to sixteen cohorts. Eventually the civil war was won by Flavius Vespasian, the conqueror of Jerusalem, whose sole recorded action with the guard was in decreasing their size back to nine cohorts. From Vespasian tillCommodus the Praetorians were not as active as before and acted more as military units during that period, due to those Emperors being fighters at heart.
In 193 AD the Praetorian Guard took their power to new heights. During the reign of Commodus thePraetorians agreed to look the other way and allowed Commodus’ assassination they also killed Commodus’ successor, Pertinax. After this the Praetorians took a massive step in power and actually auctioned off the Imperial throne to the highest bidder, this went far beyond the previous practice of receiving bribes in the form of Donativum and everyone was shocked. The man who bought the throne was Didius Julianus (a wealthysenator), but he was killed by the Praetorians in a sudden change of favor. Septimius Severus then took over that same year and disbanded the Praetorian Guard on charges of disloyalty, only to reform them later on in his reign. However Septimius Severus made a big change to the Guard by opening recruitment to all legions in the Roman Empire, not just the Italian ones. Over the course of the next century the Roman Empire was delved into near continuous chaos as political power struggles, civil war, and barbarian attacks wracked the Romanstate and the Praetorian Guard’s meddling in Imperial affairs only made things worse. Stability returned a short while with the ascension of Aurelian but this stability faded after his death in 275. The chaos returned for another decade after this and was stopped by Diocletian in 284 AD
Diocletian’s rise to power in 284 marked the beginning of the end. One of the many things that the Emperor Diocletian did in his reforms of the Roman Empire was to form a new military unit, called the ‘Sacer Comitatus’, this unit’s primarily job was to protect the Emperor. In one swift stroke Diocletian had destroyed the power of the Praetorians by taking away their primary job, protecting the Emperor, and giving it to a similar but more trustworthy unit. With their job gone the Praetorians faded and were relegated to a role on the sidelines, that is until 306 AD, when opportunity presented itself for a comeback for the Praetorian Guard. That year Constantinewas made Augustus of the West and the Praetorians, who did not like Constantine, elevated his chief rivalMaxentius to the throne. Galerius, Augustus of the East, sent a subordinate to subdue the Praetorians but this just catapulted the rest of them into supporting Maxentius. When Constantine invaded Italy in 312 AD he metMaxentius in battle for the last time at Milvian Bridge, where nearly all of his troops were Praetorian Guards. In the battle Constantine crushed Maxentius and with him the Praetorian Guard. When he arrived in RomeConstantine completely abolished the Praetorian Guard and scattered their remaining members to the far corners of the Roman Empire, he also in a symbolic gesture destroyed the Castra Preatoria, bringing 300 years of Imperial history to an end.
The organization of the Praetorian Guard was unlike the rank and file legions. As stated above the Praetorian Guards were made up of veterans from first the Italian legions, then the whole empire, this ensured the elite status of the unit. Training in the Praetorian Guard was much harder and much more intense then the regular legions, mostly due to their elite status as the Emperor’s bodyguards. Pay for a Praetorian was much higher then the regular soldier and this special pay was called Sesquiplex Stipendum which means ‘pay and a half’, it was given three times a year: January, May, and September. This pay was increased by Domitian to 1,500 denarii and fixed at that by Septimius Severus. There was also the Donativum as mentioned above which was given at the ascension of each new Emperor. A Praetorian could retire after 16 years of service (this is shorter then the 20-25 years in the rank and file) and upon this receive 5,000 denarii, some land, and a diploma (like the rank and file received).
The arms and armor of the Praetorian was pretty much the same as the rank and file. The Praetorian Guardcarried the same weapons and wore the same armor as regular legionaries during Augustus’ reign but following his death and the ascension of Tiberius things changed a little bit. For one the Praetorians were allowed to wear special breastplates and they were granted special blue shields that a bore a quarter Moon, stars and scorpions (probably because Tiberius’ birth sign was the Scorpion). It is debated however about historical authenticity of the breastplates, but shields have been found so at least that much probably distinguished them on the battle field.
In conclusion the Praetorian Guard was one of Imperial Rome’s most remembered military units. Today the term Praetorian is used to denote any exemplary bodyguard unit or military politics.