This article is about the Roman military unit. For other meanings, see Triarius.

Triarii (Singular: Triarius) were one of the elements of the early Roman military Manipular legions

Maniple (military unit)

Maniple was a tactical unit of the Roman legion adopted from the Samnites during the Samnite Wars . It was also the name of the military insignia carried by such unit....

 of the early Roman Republic (509 BC – 107 BC). They were the oldest and among the wealthiest men in the army, and could afford good quality equipment. They wore heavy metal armour and carried large shields, their usual position being the third battle line. During the Camillan era

Marcus Furius Camillus

Marcus Furius Camillus was a Roman soldier and statesman of patrician descent. According to Livy and Plutarch, Camillus triumphed four times, was five times dictator, and was honoured with the title of Second Founder of Rome....

, they fought in a shallow phalanx formation

Phalanx formation

The phalanx is a rectangular mass military formation, usually composed entirely of heavy infantry armed with spears, pikes, sarissas, or similar weapons...

, supported by light troops. In most battles triarii were not used because the lighter troops usually defeated the enemy before the triarii were committed to the battle. They were meant to be used as a decisive force in the battle, thus prompting an old Roman saying: 'Going to the triarii' (res ad triarios venit), which meant carrying on to the bitter end. They were eventually phased out after the Marian reforms

Marian reforms

The Marian reforms of 107 BC were a group of military reforms initiated by Gaius Marius, a statesman and general of the Roman republic.- Roman army before the Marian reforms :...

 of 107 BC.

History and deployment

Triarii may have evolved from the old first class of the army under the Etruscan kings. The first class comprised the richest soldiers in the legion who were equipped with spears, breastplates and large shields, like heavy Greek hoplites. They served as heavy infantry

Heavy infantry

Heavy infantry refers to heavily armed and armoured ground troops, as opposed to medium or light infantry, in which the warriors are relatively lightly armoured. As modern infantry troops usually define their subgroups differently , 'heavy infantry' almost always is used to describe pre-gunpowder...

 in the early Roman army, and were used at the front of a very large phalanx formation

Phalanx formation

The phalanx is a rectangular mass military formation, usually composed entirely of heavy infantry armed with spears, pikes, sarissas, or similar weapons...

. After a time, engagements with the Samnites and Gauls

Gauls

The Gauls were a Celtic people living in Gaul, the region roughly corresponding to what is now France, Belgium, Switzerland and Northern Italy, from the Iron Age through the Roman period. They mostly spoke the Continental Celtic language called Gaulish....

 appear to have taught the Romans the importance of flexibility and the inadequacy of the phalanx on the rough, hilly ground of central Italy.

Camillan era

By the 4th century BC, the military formations the Romans had inherited from the Etruscans were still in use. Though their efficiency was doubtful, they proved effective against Rome's largely local adversaries. When Gauls invaded Etruria in 390 BC, the inhabitants requested help from Rome. The small contingent Rome sent to repel the Gallic invaders provoked a full-scale attack on Rome. The entire Roman army was destroyed at the Battle of the Allia

Battle of the Allia

The Battle of the Allia was a battle of the first Gallic invasion of Rome. The battle was fought near the Allia river: the defeat of the Roman army opened the route for the Gauls to sack Rome. It was fought in 390/387 BC.-Background:...

. This crushing defeat prompted reforms by Marcus Furius Camillus

Marcus Furius Camillus

Marcus Furius Camillus was a Roman soldier and statesman of patrician descent. According to Livy and Plutarch, Camillus triumphed four times, was five times dictator, and was honoured with the title of Second Founder of Rome....

. Under the new system, men were sorted into classes according to wealth, the triarii being the richest after the mounted equites. Triarii were armed with spears, or hastae

Hasta (spear)

Hasta is a Latin word meaning spear. Hastae were carried by early Roman Legionaries, in particular they were carried by and gave their name to those Roman soldiers known as Hastati...

, about 2 metres (6½ feet) long. They also carried sword

Sword

A sword is a bladed weapon used primarily for cutting or thrusting. The precise definition of the term varies with the historical epoch or the geographical region under consideration...

s, or gladii

Gladius

Gladius was the Latin word for sword, and is used to represent the primary sword of Ancient Roman soldiers. Early ancient Roman swords were similar to those used by the Greeks. From the 3rd century BC, the Romans adopted swords similar to those used by the Celtiberians and others during the early...

, about 84 centimetres (29 inches) long, in case the spear broke or the enemy drew too close. They fought as hoplites, usually carrying clipei

Clipeus

In the military of classical antiquity, a clipeus was a large shield worn by the Greeks and Romans as a piece of defensive armor, which they carried upon the arm, to secure them from the blows of their enemies...

, large round Greek

Ancient Greece

Ancient Greece is a civilization belonging to a period of Greek history that lasted from the Archaic period of the 8th to 6th centuries BC to the end of antiquity. Immediately following this period was the beginning of the Early Middle Ages and the Byzantine era. Included in Ancient Greece is the...

 shields, and bronze helmet

Helmet

A helmet is a form of protective gear worn on the head to protect it from injuries.Ceremonial or symbolic helmets without protective function are sometimes used. The oldest known use of helmets was by Assyrian soldiers in 900BC, who wore thick leather or bronze helmets to protect the head from...

s, often with a number of feathers fixed onto the top to increase stature. Heavy plate armour was favoured, with mail

Chainmail

Mail is a type of armour consisting of small metal rings linked together in a pattern to form a mesh.-History:Mail was a highly successful type of armour and was used by nearly every metalworking culture....

 also being popular. Many would paint or engrave portraits of ancestors onto their shield, believing that it would bring them luck in battle.

In this type of new Roman legion

Roman legion

A Roman legion normally indicates the basic ancient Roman army unit recruited specifically from Roman citizens. The organization of legions varied greatly over time but they were typically composed of perhaps 5,000 soldiers, divided into maniples and later into "cohorts"...

, the 900 triarii formed 15 maniple

Maniple (military unit)

Maniple was a tactical unit of the Roman legion adopted from the Samnites during the Samnite Wars . It was also the name of the military insignia carried by such unit....

s, military units of 60 men each, which were in turn part of 15 ordines

Ordo

Ordo may refer to:* A musical phrase constructed from one or more statements of a rhythmic mode pattern and ending in a rest* Ordo , is a nomadic palace for the Mongol aristocrats and the Turkic rulers...

, larger units made up of a maniple of triarii, a maniple of rorarii and a maniple of accensi

Accensi

Accensi were light infantry in the armies of the early Roman Republic. They were the poorest men in the legion, and could not afford much equipment. They did not wear armour or carry shields, and their usual position was part of the third battle line. They fought in a loose formation, supporting...

. The triarii stood in the third line of the legion, behind the front line of hastati

Hastati

Hastatii were a class of infantry in the armies of the early Roman Republic who originally fought as spearmen, and later as swordsmen. They were originally some of the poorest men in the legion, and could afford only modest equipment — light armour and a large shield, in their service as the...

and the second line of principes

Principes

Principes were spearmen, and later swordsmen, in the armies of the early Roman Republic. They were men in the prime of their lives who were fairly wealthy, and could afford decent equipment. They were the heavier infantry of the legion who carried large shields and wore good quality armour. Their...

, and in front of the rorarii and accensi. In a pitched battle

Pitched battle

A pitched battle is a battle where both sides choose to fight at a chosen location and time and where either side has the option to disengage either before the battle starts, or shortly after the first armed exchanges....

, the leves

Leves

Leves were javelin-armed skirmishers in the army of the early Roman republic. They were typically some of the youngest and poorest men in the legion, and could not afford much equipment. They were usually outfitted with just a number of light javelins and no other equipment...

, javelin-armed skirmishers who were attached to maniples of hastati, would form up at the front of the legion and harass the enemy with javelin fire and cover the advance of the hastati, spear

Spear

A spear is a pole weapon consisting of a shaft, usually of wood, with a pointed head.The head may be simply the sharpened end of the shaft itself, as is the case with bamboo spears, or it may be made of a more durable material fastened to the shaft, such as flint, obsidian, iron, steel or...

 armed infantry. If the hastati failed to break the enemy, they would fall back and let the principes, heavier and more experienced infantry, take over. If the principes did not break them, they would retire behind the triarii, who would then engage the enemy in turn—hence the expression rem ad Triarios redisse, "it has come to the triarii"—signalling an act of desperation. The equites, cavalrymen, were used as flankers and to pursue routing enemies. The rorarii, the poorer reserve soldiers, and accensi, the least dependable troops armed with sling

Sling

The word sling may refer to:* Sling , a device used to hurl projectiles* Sling is an item of climbing equipment consisting of a sewn loop of webbing that can be wrapped around sections of rock or tied to other pieces of equipment.* Sling * Ski jumping sling is an item of sports training...

s, would be used in a support role, providing mass and supporting wavering areas of the line.

Polybian system

By the time of the second Punic war

Second Punic War

The Second Punic War, also referred to as The Hannibalic War and The War Against Hannibal, lasted from 218 to 201 BC and involved combatants in the western and eastern Mediterranean. This was the second major war between Carthage and the Roman Republic, with the participation of the Berbers on...

 of the late 3rd century BC, this system proved inefficient against enemies such as Carthage

Carthage

Carthage , implying it was a 'new Tyre') is a major urban centre that has existed for nearly 3,000 years on the Gulf of Tunis, developing from a Phoenician colony of the 1st millennium BC...

. After a series of more "organic" changes as opposed to a single intentional reform, a new system gradually came into being. Infantry were sorted into classes according to age and experience rather than wealth, the triarii being the most experienced. Their equipment and role was very similar to the previous system, except they now carried scuta

Scutum (shield)

Scutum is the Latin word for "shield", although it has in modern times come to be specifically associated with the rectangular, semi-cylindrical body shield carried by Roman legionaries.-History:...

, large rectangular shields that offered a greater degree of protection than the old round clipeus.

The number of triarii had been reduced to 600 per legion, now forming 10 maniples of 60 men each. The triarii still made up the third line in the legion, behind the front line of hastati and the second line of principes, but the rorarii and accensi had been phased out. Leves had been replaced with velites

Velites

Velites were a class of infantry in the Polybian legions of the early Roman republic. Velites were light infantry and skirmishers who were armed with a number of light javelins, or hastae velitares, to fling at the enemy, and also carried short thrusting swords, or gladii for use in melee...

, who had a similar role but were also attached to principes and triarii. Pitched battles were conducted in a similar fashion: the velites would gather at the front and fling javelins to cover the advance of the hastati. If the hastati failed to break the enemy, they would fall back on the principes, who now carried swords rather than spears. If the principes could not break them they would retire behind the triarii, who would then engage the enemy.

This order of battle was almost always followed, the battle of the Great Plains

Battle of the Great Plains

The Battle of the Great plains was a battle fought between Scipio Africanus of Rome and a combined Carthaginian and Numidian army late in the Second Punic War, designed as diversionary tactic by Rome to disrupt Hannibal's attack on Italy...

 and the battle of Zama

Battle of Zama

The Battle of Zama, fought around October 19, 202 BC, marked the final and decisive end of the Second Punic War. A Roman army led by Publius Cornelius Scipio Africanus defeated a Carthaginian force led by the legendary commander Hannibal...

 being among the few notable exceptions. At the Great Plains, Scipio, the Roman general, formed his men up in the usual manner, but once the hastati had begun to engage the enemy, he used his principes and triarii as a flanking force, routing the opposing Carthaginians. At Zama, Scipio arranged his men into columns, side by side, with large lanes in between. The opposing Carthaginian elephants were drawn into these lanes where many were killed by velites without inflicting many casualties on the Romans. Once the surviving elephants had been routed, he formed his men into a long line with his triarii and principes in the centre and hastati on the flanks, ready to engage the Carthaginian infantry.

Marian reforms

With the formal military reforms

Marian reforms

The Marian reforms of 107 BC were a group of military reforms initiated by Gaius Marius, a statesman and general of the Roman republic.- Roman army before the Marian reforms :...

 of Gaius Marius

Gaius Marius

Gaius Marius was a Roman general and statesman. He was elected consul an unprecedented seven times during his career. He was also noted for his dramatic reforms of Roman armies, authorizing recruitment of landless citizens, eliminating the manipular military formations, and reorganizing the...

 in 107 BC, implemented to combat a shortage of manpower due to wars against Jugurtha

Jugurtha

Jugurtha or Jugurthen was a King of Numidia, , born in Cirta .-Background:Until the reign of Jugurtha's grandfather Masinissa, the people of Numidia were semi-nomadic and indistinguishable from the other Libyans in North Africa...

 in Africa and Germanic tribes to the north, the different classes of units were scrapped entirely. The wealth and age requirements were removed; anyone could join as a career, rather than as service to the city, and all would be equipped as milites

Legionary

The Roman legionary was a professional soldier of the Roman army after the Marian reforms of 107 BC. Legionaries had to be Roman citizens under the age of 45. They enlisted in a legion for twenty-five years of service, a change from the early practice of enlisting only for a campaign...

, with the same, state-purchased equipment. Auxiliaries

Auxiliaries (Roman military)

Auxiliaries formed the standing non-citizen corps of the Roman army of the Principate , alongside the citizen legions...

, local irregular troops, would fulfill other roles, serving as archers

Archery

Archery is the art, practice, or skill of propelling arrows with the use of a bow, from Latin arcus. Archery has historically been used for hunting and combat; in modern times, however, its main use is that of a recreational activity...

, skirmishers and cavalry

Cavalry

Cavalry or horsemen were soldiers or warriors who fought mounted on horseback. Cavalry were historically the third oldest and the most mobile of the combat arms...

. Sallust, in his Jugurthine War, describes several instances in which Roman or allied regular heavy infantry were equipped with light equipment and used as light footsoldiers. This was supposedly a common practice.