The Roman Legionnaire

Welcome to part two of the series on the most interesting and famous fighting units of ancient history, where we will be looking at the mighty Roman Legionnaire. Highly trained and well-equipped, the legionnaire defended and expanded the lands of arguably the most powerful and famous civilization in human history. Recognized as one of the most renowned soldier units of all time, the legionnaire was the first truly professional soldier, and is regarded as the perfect model for efficient and able warfare.

Part 1 - Greek Hoplite

Part 3 - Japanese Samurai

Part 4 - The Swiss Pikeman

The Roman legionnaire, a heavy infantry soldier, was the basic fighting unit of the Roman Republic, and then Empire for over 500 years. This long period of time is usually broken down into 3 parts –the Marian era (107-30 BC), the Imperial era (30 BC-284 AD) and finally the Late Imperial era (284-476 AD). The one thing that united all legionnaires throughout this long period of time is that they were Roman citizens under the age of 45.

Prior to 300 BC, the Roman army was fashioned almost entirely on the Greek Hoplite phalanx, discussed in detail in the first hub of this series. From 300 to 107 BC, the Roman army underwent several changes. The legions were first introduced, breaking down the army from one single phalanx mass, and there was a great change in strategy and organization. However, the titular Roman Legionnaire would not truly come into being until 107 BC.

Marian Era (107-30 BC)

The Marian period is highlighted by the military reforms of the Roman general Gaius Marius. The first important change was that people were no longer required to be a high-class citizen with a decent amount of land to qualify for service. Instead, the only requirement was that you had to be a Roman citizen. Second, the Roman army truly became professional. Whereas prior to 107 BC legions were conscripted when needed, and then disbanded, the legions were now recruited on a volunteer basis, and functioned year-round. This meant that men serving in the legions had standard pay, and were considered to be employed by the state. Third, the infantry distinction created roughly between 300-107 BC was now officially removed. Instead of three different types of infantry serving in the Roman legions, there was now only one – the Roman legionnaire. Lastly, all legionnaires were now provided with equipment instead of having to buy it themselves.

Imperial Era (30 BC-284 AD)

The Imperial period marked the end of the Roman Republic, and the beginning of the Roman Empire, as Augustus, the first Emperor, rose to power. Augustus went further in making the Roman legions even more potent and professional. He disbanded half the legions, removing all the conscript-based men who were acquired during the Civil War, and raised the serving term to 25 years. This meant that the legions were now a fully professional army of volunteers. There were also ongoing changes in how the smaller units of each legion were organized.

This period of time is further significant for the changes in the racial background of Roman legionnaires. As the Roman Empire grew in size, less and less legionnaires were of direct Italian descent, and more of them were conquered barbarians, especially after Emperor Caracalla decreed in 212 AD that all free men within the Roman Empire were now Roman citizens. Lastly, the image of legionnaires of this time period is how most of the world portrays them today.

Late Imperial Era (284-476 AD)

The Late Imperial period saw a big change for the legionnaires. As the Roman Empire weakened (eventually breaking up into two halves in 395), the pay for soldiers decreased, and more barbarians were recruited into the army. Involuntary conscription also returned several times throughout this period. Furthermore, the army was broken down into standing forces and border troops, as the Empire now sought to keep its lands rather than expand them. The look of Roman legionnaires themselves gradually changed from the Imperial to a more medieval European soldier – the shields got rounder, the swords and javelins longer, and mail started to replace the segmented armor. Finally, as the Western Roman Empire gasped its last breath, so did the legionnaire - the soldier unit would never return again.

While the Roman legionnaire’s equipment, strategy, and background changed throughout this long period of time, some things remained the same – legionnaires were always organized in legions, groups of up to 6,000 men. Typically numbering between 25 and 40, the legions were the main component of the Roman army.

Each legion was lead by a "Legate" commander, and broke down into many smaller components. Although these once again varied over time, the general breakdown was as follows: Legion – cohorts – centuries. Each legion usually comprised of ten cohorts, ranked 1 through 10 in seniority and prestige. Each cohort then comprised of six centuries, while each century comprised of anywhere from 60 to 100 men, commanded by the aptly-named centurions. The most senior of these centurions was believed to command the entire cohort. Lastly, each century was broken down into roughly 10 groups of 8 men each – the contubernium. Each contubernium lived in the same tent, and functioned as a unit, with its own officer. As you can see, there was a very high degree of control due to the large number of officers - men could be commanded both at the legion level, and the smaller levels.

The Engagement

Legionnaires were typically placed in the middle of the army, with relatively small cavalry groups on their flanks. Each legion (however many there were at the given battle) would then march together in cohorts, each cohort in a rectangular formation. While historical sources are not conclusive, most historians seem to share the view that these cohorts approached the battle in a quincunx formation. When they were closer to the enemy, a solid front line of legionnaires would be formed and begin their push, while the cohorts behind them would move closer together and reduce the gaps between them, forming two layers with thin gaps.

The front line would then attack and push the enemy back, while continually being relieved by cycling men from the two layers behind it. This was done so that the soldiers from the front line could rest, and then come back when their turn was up again. Once the battle started, the cohorts could break down into smaller groups depending on the demands of the battle, as the large number of various officers allowed for great control and cohesion throughout the whole legion. These smaller groups could then be deployed wherever needed and in whatever fashion; this mobility and adaptability was a huge bonus. This smart and highly organized battle strategy eventually wore down the opponent and insured victory.

Main Tactical Formations

The Tortoise

In a battle, Roman legionnaires could employ a number of important strategies. Perhaps the most famous of these is the “Tortoise”. The Tortoise was a defensive formation, in which the legionnaires in the front line would hold their large shields up in front, while all legionnaires behind them would hold their shields up vertically above their heads. This formed a turtle-like shell around the moving group of legionnaires, and was used to defend from long range missile attacks, mostly from bowmen and javelin throwers. Once the legionnaires were in melee range with the enemy’s infantry, they could go back to their normal formation. This was due to the fact that the enemy’s ranged forces would not risk damaging their own soldiers at such close distance.

The Wedge

The Wedge was an offensive formation, where legionnaires would form a triangle. At the tip would be one legionnaire. This was a very popular and successful offensive maneuver for small groups of legionnaires – multiple wedges could be thrust into the enemy line, and then expanded outwards to push the enemy and give them little room to actually fight back. This was especially effective since the legionnaires used the short gladius sword, which was perfect for very small-space, close-quarter combat, where as many of their enemies used very large, long weaponry.

Repel Cavalry Formation

This formation was made specifically to combat cavalry (men on horseback). The front line of the given legion sub-unit would form a wall with their shields, and protrude their javelins outward. This would scare horses and they would refuse to run into the formation. The lines behind these legionnaires would then throw their own javelins at the cavalry, as they attempted to ride away.

The Orb

The Orb was a relatively desperate defensive position, deployed only when a unit of legionnaires was surrounded by enemy forces. Legionnaires would form a circular position, defending themselves from all sides. The officer of the group would be positioned in the middle of the orb, relatively safe to give out orders.

While Roman legionnaires may not have been known for their ferocity, they were definitely known for a high amount of discipline and endurance. The Romans trained their legions constantly with discipline being at the core of their military ideology. Legionnaires were trained on how to use weapons and shields, march together, follow orders, and execute various maneuvers, in order to be able to work together as a well-oiled machine. In addition to all of this, they had constant physical training to build physical and mental strength.

Marian and Imperial Period (107 BC - 284 AD)

The most important and without a doubt iconic piece of the Roman legionnaire's gear was the “scutum” - the shield. In the Marian period the scutum was of an oval shape, while in the imperial period the scutum became a large, yet light rectangular shield which curved outwards, typically around 1 meter in height. The scutum was specifically designed not only to defend against close-quarter combat, but also against missile attacks. Its shape and size also made it very practical when deployed in groups of legionnaires, where the shield of each man played a role in an entire formation.

The primary weapon was the gladius, a short sword made for both cutting and thrusting, with an average length of 70 cm. The gladius was primarily used to thrust out from behind the scutum. The secondary weapons were a dagger, kept in case of losing the sword, and 2 javelins, one about 1 meter and the other 2 meters long, which were typically used to throw at the enemy right before melee combat.

The body armor during the Marian period typically consisted of a mail shirt. The imperial period on the other hand was dominated by the Lorica Segmentata type of armor – pieces of iron armor segmented together and tied by leather at the front and the back. Helmets also tended to change over time, from a simpler design in the Marian to the more sophisticated designs of the Imperial and late Imperial periods. They were typically made from bronze, iron, or brass.

Late Imperial Period (284 - 476 AD)

As noted earlier, the late Imperial period legionnaire equipment had a much more medieval look to it, and in a sense was a precursor to the gear used in Europe during the Middle ages. The shields slowly grew into an oval, and then a circular shape, the gladius was replaced by longer swords, the javelin replaced by a longer spear, and the segmented armor replaced by mail.

The main legacy of Roman legionnaires is that Roman civilization was defended, and expanded its borders throughout their half-millennium-long service. The legionnaire was an incredibly efficient, disciplined and powerful fighting unit, especially during the main Imperial period of Roman history, where Rome saw its biggest territorial expansion. As such, the legionnaire is significant for greatly influencing the art of warfare and for Rome's success as an Empire.