The Roman army has been known in history as a very skilled and disciplined army throughout Ancient Rome, which was able to conquer many areas of the ancient world. At its largest, the Roman army was made up of 30 legions, or over 150,000 soldiers. Counting the auxiliary soldiers, some estimate there were well over 1 million soldiers in the Roman army, so it really was a military force to be reckoned with.
To make up this army, the Romans had various types of soldiers with different skills for different purposes.
Joining The Army
Roman soldiers were all men, and those in the Roman Legionary were all Roman citizens. They had to be at least 1.7m tall and in good health to join the army. They were interviewed and given a medical examination. If they were successful they were required to swear an oath of loyalty to Rome and the Emperor. They would then be assigned to a legion and sent to their posting.
New soldiers were put through vigorous training to ensure that they became proficient fighters. This training included not only combat techniques but also skills such as carpentry, road building and swimming. Roman soldiers were expected to march up to 20 miles per day in line, wearing all their armor and carrying their food and tents. The average legionary carried at least 90 pounds of weight, so they had to be in good shape and trained well.
There were two main types of Roman soldiers: legionaries and auxiliaries.
The legionaries were the elite soldiers. A legionary had to be over 17 years old and a Roman citizen. Legionaries signed up for at least 25 years service, and at the end of the 25 years, they were generally awarded land they could farm and/or a large sum of money. Old soldiers often retired together in military towns, called ‘colonia’.
This system ensured that the Roman army was made up of trained and experienced soldiers.
A legionary’s basic pay was about 300 denarii (silver pieces) a year, but out of this they had to pay for part of their food, equipment, pension and funeral savings. The balance of what was left was paid to the soldiers every three months or so.
An auxiliary, on the other hand, was a soldier who was not a Roman citizen. They were only paid a third of a legionary’s wage, and they generally did the most dangerous jobs.
Auxiliaries guarded forts and frontiers but also fought in battles, often in the front lines. Once an auxiliary had served in the army for 25 years, they could become a citizen of Rome.
The formation of the Roman army was fairly simple. At the top of the military hierarchy was the Praetorian Guard. This was the bodyguard for the Emperor and they only took to the battlefield when led by the Emperor in person. They were normally based in Rome.
The army was divided up into legions, with each legion compose of 10 cohorts, each containing 480 men. However, the first cohort had double that number. This meant there were around 5,280 men (legionaries) in a legion. Each cohort was then subdivided into six centuries of 80 men controlled by a centurion. The centuries would then be divided into smaller groups with different jobs to perform.
The make-up can be seen more easily when laid out:
- 10 cohorts to one legion
- six centuries to one cohort
- 10 tents to one cohort
- eight soldiers to one tent
Attached to the legions was a small body of horsemen whose main duties were those of dispatch riders and guards. There were also many specialist men who travelled with the troops, including included clerks, armorers, blacksmiths, stone-masons, carpenters and medical staff. Each legion also had its own architect and water engineer, whose job it was to find suitable sites for the temporary and permanent forts of the army. These men were regarded as technicians, not fighters.
Within the auxiliaries, there were four main forms of force:
- Alae quingenariae; one ala of 16 turma; one turma of 30 men; 480 men.
- Infantry cohort; one cohort of six centuries; one century of 80 men; 480 men.
- Cohorts equitates; mixed infantry and cavalry. The auxiliaries were commanded by prefects of the equestrian rank. However, as the auxiliaries developed, a fourth kind of troop was introduced, which reflected the fact that the auxiliaries had developed into a status very similar to that of the legionaries.
- Numeri; from the 2nd century CE onwards. They were formed from local tribes, around 500 men, and they did not have to speak Latin. They often fought in keeping with their local tradition.
Within the legion, there were different ranks. They were as follows, from highest to lowest:
- Legatus legionis; an ex-praetor
- Six military tribunes: one tribunus laticlavius, who aided the legate and was second in command and would have been of senatorial rank; five tribuni augusticlavii of equestrian rank.
- Praefectus castorum; dealt with camp logistics; took control if the Legatus legionis and tribunus laticlavius were absent
- 60 centurions; with their own rankings, as follows:
- For 2nd-10th cohorts of a legion; six centurions: pilus prior, princeps prior, hastatus prior, pilus posterior, princeps posterior, hastatus posterior (highest to lowest)
- Forfirst cohort; five centurions (primi ordines): primus pilus, princeps prior, hastatus prior, princeps posterior, hastatus posterior (highest to lowest)
Equipment and Weapons
The legionaries were equipped with armor to protect themselves while fighting. In the early period this armor consisted of a hardened leather jerkin (vest) which was reinforced with metal plates. However, it was later replaced with metal strip armor, which went to the hip. From the hip to the knee the soldiers wore either a heavy woollen tunic or an apron made of leather and bronze strips hanging from a belt.
They wore helmets, too, which were domed and had hinged cheek pieces to protect the face. Officers, such as centurions, wore large crests on their helmets. This allowed the soldiers to see them better in battle.
Legionaries also had shields, which were semi-cylindrical. When held to the body, these covered from the chin to the thigh along the whole of one side, giving them a good amount of protection. They were made from light wood bound at the edges with metal with a strong central bronze boss for the internal hand grip.
In terms of weapons, the solders fought the pilum (javelin) and the gladius (short sword). The pilum was made of wood and around 7ft long with an iron tip. A legionary carried two of these each. They were designed to throw at the enemy up to 30m away, piercing the enemy’s shield. They would then be difficult to pull out of the shield, thanks to the iron tip, forcing the enemy to abandon their shield. The soldiers could then use their gladius to fight the enemy in close combat.
In later years, the spatha was used. A spatha was a longer sword closer to a meter in length. This weapon was used by some auxiliary units during the early Roman Empire and later used by legionary infantry in the third century CE and later. A dagger (pugio) was also used. It originated from the Iberian peninsula. It was usually fifteen to thirty centimeters long and five centimeters wide. The pugio would be used in very close quarters combat when a soldier had either lost or was unable to use his gladius.
The Romans usually lined up for battle in a tight formation. They would march at a slow steady pace towards the enemy and then, at the last minute, hurl their javelins.
They would then charge at the enemy with their swords. They had been taught to fight at close proximity to their enemy, where their short swords were most effective.The main “frontal” attacks were carried out by the legionaries, while the auxiliaries fought at the sides. The Romans also used cavalry to chase enemies who tried to run away.
There were three main tactics used by the Romans when fighting. The first was known as the testudo, or ‘the turtle’, and involved the front rank of the formation kneeling behind their interlocked shields, over a metre in height, while the second rank held their shields above the heads of the men in front, and so on. This allowed them to present a 360-degree wall of wood to opponents.
The second was known as the triple line, and involved three lines of soldiers, which could often stretch for more than a mile. Formations were made based on military rank. The lines consisted of the least experienced men, the hastate, at the front followed by the principles and then the triarii, or the most experienced soldiers. In front of all of them were the velites, the newest and poorest recruits, whose job it was to attack the approaching enemy with javelins. The three lines could often stretch for more than a mile.
The third tactic was the wedge. This was a v-shaped formation that allowed the soldiers to turn more easily than in a square one, as everyone was following he leader at the apex. The point, or the center of the wedge, was made up of lines of the best troops available. The wedge shape also allowed the Romans to drive into the enemy with more force than if they were in a straight line.
History of The Roman Army
Early Roman Army (c. 500 BC to c. 300 BC)
The early Roman army were the army during the Roman Kingdom and of the early Roman Republic. It has been said that this army followed Etruscan or Greek models of organisation and equipment. This army consisted of 3,000 infantrymen and 300 cavalrymen, and the army was based on an annual levy. The population was split into five classes, each of which would have different roles in the military.
The first class could afford to have a cuirass (upper body armor), greaves (a piece of armor used to protect the shin), a shield, a sword, and a spear, while the second class had greaves, a shield, a sword, and a spear.
The third class could only afford to have the shield, a sword, and a spear, and the fourth class could only afford a shield and a spear. The fifth class would only be slingers. Any poorer citizen, called Capite Censi, would have no weapons, and they would not serve in the army unless it was an emergency.
Roman Army of the mid-Republic (c. 300–88 BC)
The Roman army of the mid-Republic was also known as the “manipular army”, or the “Polybian army”, after the Greek historian Polybius, who provides the most history of the army during this time. During this time, the Roman army started to have a full-time strength of 150,000 men at all times and 3/4 of the rest were levied.
When Gaius Marius was elected consul in 107 BC, he began to enlist volunteers from citizens without property and equipped them with arms and armor at the expense of the state. The Social War of 91–87 BC highlights that manpower was still a problem for the Roman army, as citizenship was granted to the allied Italians at the end of the war, giving a greater pool of men for the army.
Roman Army of the late Republic (88–30 BC)
During the late Republic, the army continued to transition from conscription based soldiers to soldiers who had volunteered to fight. While regular annual conscription remained in force and continued to provide the most amount of soldiers, an ever-increasing proportion of recruits were volunteers, who signed up for 16-year terms as opposed to the maximum 6 years for conscripts. Large numbers of heavy infantry and cavalry were recruited in the Roman Provinces of Hispania, Gallia and Thracia, and archers from the Eastern Mediterranean.
Imperial Roman Army (30 BC–AD 284)
Around the beginning of Imperial Rome, the first Roman emperor Augustus reorganised the Roman army, increasing the length of service to 20-year terms, although many soldiers would serve as many as 30 to 40 years on active duty. The regular annual conscription of citizens was abandoned and only allowed in emergencies.
Under Augustus, there were 28 legions, consisting almost entirely of heavy infantry, with about 5,000 men each (total 125,000). Legions were flanked by the auxilia, who were made up of volunteers of those who did not hold Roman citizenship. Auxiliaries held a minimum term of 25 years.
Later Roman Army (284–476 AD)
During the period of Emperor Diocletian (who ruled 284–305 AD), the Roman army returned to regular annual conscription of citizens, while admitting large numbers of non-citizen barbarian volunteers.
However, soldiers remained 25-year professionals and did not return to the short-term levies of the Republic. The old dual organisation of legions and auxilia was abandoned, with citizens and non-citizens now serving in the same units. The old legions were broken up into cohorts or even smaller units.
The Roman Army and Britain
The overall size of the Roman forces in Roman Britain grew from about 40,000 men in the mid 1st century AD to a maximum of about 55,000 men in the mid 2nd century. By the mid-2nd century, there were about 70 auxiliary regiments in Britain, for a total of over 40,000 men. These outnumbered the 16,500 legionaries in Britain (three Roman legions) by 2.5 to 1.
The Roman conquest of Britain began in AD 43 under Emperor Claudius. He appointed Aulus Plautius, a distinguished senator to lead an army of 40,000 men consisting of 4 legions and 20,000 auxiliaries. The four legions were Legion II Augusta, Legion IX Hispania, Legion XIV Gemini, and Legion XX Valeria Victrix.
At first, Camulodunum (modern day Colchester) was taken, but between 43 AD and 47 AD, the Romans continued their conquest and by 47 AD had conquered the whole of South Britain and claimed Britain as part of the Roman Empire. Londinium (modern day London) was founded by the Romans following this, and a bridge built across the river Thames.
The British who remained after the Roman conquering lived fairly peacefully with the Romans, until around 61 AD when Prasutagus, King of the Iceni tribe who had signed a peace treaty with the Romans, died. Following his death, the Romans ignored the treaty and took his land. Boudica, who was Prasutagus’ wife, decided to lead an uprising against the Romans. This led to Boudica’s uprising, which has been well-known throughout history. However, Boudica was defeated and Colchester, London and St Albans were burned.
Under the command of Gnaeus Julius Agricola, between AD 70 and 80, the Romans extended their control of England, particularly into the north and west. After most of England had been conquered, the legions settled into 3 permanent locations — York in 71 AD, Caerleon 75 AD (south east Wales) and Chester in 79 AD.
Agricola and the Romans then moved northwards defeating the Caledonian tribes under the leadership of Calgacus at the battle of Mons Graupius in present day northeastern Scotland. Then, in 122 AD, the emperor Hadrian ordered the construction of a wall from the west coast of Britain to the east, known famously as Hadrian’s Wall.
Hadrian’s Wall ran for eighty miles from Newcastle in the east to Carlisle in the west. Designed to mark the boundaries of the Roman Empire, much of the great monument can still be seen today. Roman troops were scattered along the Wall.
When Hadrian died in 138 AD, his successor, Antonius Pius, abandoned the newly completed wall and decided to build a new frontier, the Antonine Wall, which was established between the Forth and Clyde rivers in Scotland. Around 160 AD the Antonine Wall was abandoned and thereafter Hadrian’s Wall again became the northern boundary of the Roman Empire in Britain.
Despite their success throughout Britain, the Roman army never succeeded in capturing the whole of Britain. Most people in the south of the country lived under Roman rule, and towns were created, such as York, Chester, St. Albans, Bath, Lincoln, Gloucester and Colchester. Much of society was Romanized, and the Romans remained in rule until the end of the 4th century.
Major Victories and Defeats of The Roman Army
The Roman army fought in many battles throughout their time. Let’s take a look at some of the most famous of these battles.
The Battle of Zama was fought in 202 BC near Zama, now in Tunisia, and marked the end of the Second Punic War. A Roman army, led by Publius Cornelius Scipio defeated the Carthaginian army led by Hannibal. This battle ended both Hannibal’s command of Carthaginian forces and also Carthage’s chances to significantly oppose Rome.
The Battle of Carthage took place in 146 BC. Under the treaty ending the Second Punic War, signed after the Battle of Zama, Carthage had to seek Roman permission before waging war. That treaty expired in 151BC, so when Rome’s ally Numidia annexed land from Carthage, a Carthaginian army marched to defend it. Rome declared this event to be an act of war and sieged Carthage. Carthage was ultimately defeated.
The Battle of Alesia, also known as the Siege of Alesia, took place in September 52 BC. Roman forces under the command of Julius Caesar besieged Alesia, a major centre of the Mandubii tribe. The battle was against a confederation of Gallic tribes united under the leadership of Vercingetorix of the Arverni. It was the last major engagement between Gauls and Romans, and is considered one of Caesar’s greatest military achievements.
Caesar directed his troops to erect a series of extensive fortifications, including two walls encircling the city, to keep the defenders in and potential reinforcements out. Vercingetorix’s eventual surrender secured Roman authority over Gaul in its entirety.
The Battle of the Milvian Bridge took place between the Roman Emperors Constantine I and Maxentius on 28 October 312. Constantine won the battle and become the sole ruler of the Roman Empire. Maxentius drowned in the Tiber during the battle; his body was later taken from the river and decapitated, and his head was paraded through the streets of Rome on the day following the battle before being taken to Africa. A year later Christianity was legally recognised and tolerated by Rome.
The Battle of Watling Street was the final battle of Boudica’s revolt against Roman rule in Britain. It happened in either 60 or 61 AD and ended Boudica’s uprising, which she had begun in response to Roman rule of her late husband’s (King Prasutagus) land following his death.
When he died, he left his lands to be divided between his daughters and the emperor, Nero. However, the Romans ignored Prasutagus’ will and seized his lands, resulting in Boudica’s uprising. In the battle, Boudica was killed and this marked the end of resistance to Roman rule in southern Britain, which was to last until 410.
The Battle of Cannae was a major battle of the Second Punic War, and took place on August 2, 216 BC near the town of Cannae in Apulia in southeast Italy. The Carthaginian army, led by Hannibal, destroyed the Roman army under command of the consuls Lucius Aemilius Paullus and Gaius Terentius Varro. Following the Battle of Cannae, Capua and several other Italian city-states defected from the Roman Republic. This battle is regarded as one of the greatest tactical feats in military history and one of the worst defeats in Roman history.
The Battle of Teutoburg Forest took place in 9 AD and was a conflict between the Roman Empire and Germanic insurgents. The Germanic leader Arminius organized a series of ambushes on a three Roman legions headed by Publius Quinctilius Varus.
Over the course of four days Arminius destroyed all three legions and ultimately prevented Rome from holding the Germanic land across the Rhine River. It was one of the two greatest disasters in Roman military history, the other being the defeat at Cannae.
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Link will appear as Hanson, Marilee. "The Roman Army" https://englishhistory.net/romans/the-roman-army/, June 13, 2022