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Marian reforms

This post is also available in: Polish (polski)

Roman legionaries from the times of the Republic
Roman legionaries from the times of the Republic | Author: Radu Oltean

In the beginning, it should be clearly emphasized that none of the preserved ancient sources says anything about the so-called Marius’ reforms. Such a term, however, appears in history, due to the transformations that took place in the Roman army, and of which certainly was Gaius Marius himself, consul holding his office since 107 by 101 BCE, Marius, who had just returned from a victorious campaign against the Numidian King – Yugurt had to prepare the Roman army to repel the invasion of the Cimbrii and Teutons.

Recruitment problems

Gaius Marius. He went down in history as a great reformer, who marked the history of the Roman republic by improving the Roman army.

In history, there has been a perception that after the Second Punic War, demographics emerged in Italy that led to the crisis in the Roman army. The source of the Roman military crisis was to be the socio-economic changes of the turn of the second and first centuries BCE. As a result of the policy of conquests, which caused an influx of slaves, rich landowners created powerful latifundia, offering low grain prices. In this way, small landowners were not able to compete and were impoverished (often their farms were taken over); as a result, potential recruitment resources have shrunk. In the 130 and 120 BCE, the brothers Tiberius and Gaius Gracchus tried to oppose such developments. However, both of them were murdered on the initiative of Optimates.

Modern historians almost agree that the Gracchus have exaggerated the problem or practised demagogy to a large extent. The crisis was certainly not so serious, as evidenced by archaeological research. After defeating Carthage in the Second Punic War, the Italian peoples who supported the Hannibal (mainly the south of the Apennine Peninsula) were punished by Rome by taking away some of the lands that were nationalized and then transferred on lease. It was here that powerful latifundia developed, on which slave groups worked. Central and northern Italy were still dominated by small landowners (so-called assidui). This is evidenced by the census carried out at the turn of 136-135 BCE – 317 993 men capable of fighting in the Roman army. This was a sufficient number to defend the state and conduct military operations, especially considering the fact that Rome did not have even 300,000 adult men during the Second Punic War (of which about 60% of the people were mobilized).

What bothered the Roman army the most in the second half of the 2nd century BCE was the recruitment problem. Many Romans avoided mobilization due to a lack of service profits and numerous wars. In response, the Senate sought to extend the mandatory period of service to maintain adequate strength. This, however, caused a decrease in morale and the widespread reluctance of men who should have returned to their farms and cultivated the land after the war ended. The fatigue with constant fighting and war campaigns was clear.

Enlist volunteers

In history, the belief that Gaius Marius transformed the Roman army from universal to professional was established. However, this is not true1. Marius, like other Roman commanders of that period (e.g. Scipio the Younger) had to deal with recruitment problems. However, he did not completely abandon universal conscription and citizens with appropriate property census2, i.e. those who owned landed property, were recruited to the army. Conscription continued after the Sulla, Lucullus or Pompey at the beginning of the 1st century BCE. However, in the face of the enormous threat of Cimbri and Teutons, Marius decided to volunteer haul, thus being able to stand up to the barbarian masses. This practice was later followed by subsequent leaders.

Such a change of approach provided for enlisting citizens without land, so-called proletaria (proletarians). As a reward for good service, which usually lasted 16 years (miles emeritus), they could receive a land allocation. Officially, the soldier received a small but regular pay of 5 asses per day and basic equipment. It should be mentioned that the dissemination of the equipment was not solely a result of Marius’ reforms. It was a slow process, which resulted rather from the influx of the poor to the Roman army, which required state support in providing weapons. The beginnings of this process can be traced to lowering the census since the Second Punic War. The evidence for these claims are archaeological findings that indicate the mass production of weapons (especially helmets) that only the state could afford.

What was undeniable, however, was the fact that the reform brought great popularity to Gaius Marius among the poor. The chief reached out to people without assets who decided to risk their own lives and health for any income. The Roman army, which in the second half of the 2nd century BCE suffered from a lack of soldiers, could now be constantly supplemented by the lowest social strata for which military service was the only chance to survive and raise capital for the future.

Changes in the structure of the Roman army

Two soldiers, designated as aquilifer (left and middle), lead their legions.
On Creative Commons Attribution license - On the same terms 3.0.

To increase the combat value of the Roman army, it was decided to divide it into its component parts. The main operating unit was the legion, which was henceforth to be the majority of heavy infantry formation. Sextus Pompey Festus reports that Gaius Marius increased the number of the legion to 6200 people, which, however, resulted rather from the need to fight the numerical opponent3 .

The legion was divided into tactical units – the so-called cohorts, which were the basic tactical units. It should be mentioned here, however, that cohorts have been in use before and are not a complete innovation of Marius. The cohorts were already used by the Italics who supported the Roman army. Interestingly, they often constituted the majority of the Roman army on the battlefield – therefore it could be said that the cohort system dominated. The cohort also used the Scipio African Elder or they took part in the wars on the Iberian Peninsula. Gaius Marius was a Roman commander who popularized their use due to great victories over Teutons and Cimbrii.

Returning to the structure – the cohort consisted of three manipulators, or six centuriae (about 600 soldiers). One legion had 10 cohorts. Also included in the cohort are velites (120 in number), which previously only played an auxiliary role on the legion scale. The light infantry thus became a full-fledged part of the cohort and its role partially increased. It should be mentioned that velites have lost their significance since the Second Punic War. The inclusion of light infantry into the ordinary line of troops was a natural process that ended at the consulate of Gaius Marius.

The first legion cohort was usually composed of the best soldiers and constituted an elite in the legion. In general, the prestige of the cohort increased the closer it was to the “first” cohort. Marius introduced one type of legion mark – eagle (aquila) – the symbol of Jupiter, which became the main mark of each legion. From that moment, the Roman army was always accompanied by this symbol. Legionaries grouped around the eagle in battle, on a march, or in a camp. The loss or loss of an eagle in combat was considered an extremely shameful thing for the whole unit. In the first cohort of each legion, a soldier was responsible for the legionary mark. He was called aquilifer. It was an extremely honorable function and valued by soldiers.

There have also been numerous changes in the war formation itself. The number of three lines remained unchanged, but now it was made up of individual cohorts: 4 in the first line, 3 in the second and third. However, depending on the situation, the Romans could fight with one or even four battle lines (acies simplex, acies duplex etc.). It should be noted that in this way an extremely flexible and universal army was achieved.

It was generally believed that Marius also unified the equipment of Roman troops. As mentioned earlier, entering the Roman army of the poor (we have been talking about this since the Second Punic War) required soldiers to be armed by the state. This in turn gave birth to mass production and similar equipment. Gaius Marius only increased the level of dissemination of the same type of weaponry among the infantry, indirectly eliminating the division into triarii, principes and hastati. Officially, however, this division was not abolished. It should be emphasized that the helmet has gained popularity, especially the type Montefortino. Chainmail, although long, was also widely used. Greaves disappeared, worn only by centurions. The pilum, scutum and gladium were used, plus the dagger (pugio). Each soldier must have two pila, light and heavy.

The Plutarch of Cheronei attributed Gaius Marius to innovation in the javelin. The modification consisted in replacing one of the metal rivets connecting the shaft with a wooden dowel. When the pilum hit the target, the stem hung only on one rivet and the javelin could not be thrown away.

Gaius Marius was also to abandon the use of citizen cavalry and foreign driving; however, it is possible that it was still in use during the battle of Pharsalus in 48 BCE.

Rolling stock reduction

“Mules of Marius” sometimes carried from 33 to 44 kilograms on their backs. After hard training and daily military drill, the legionaries were able to march with such a load of up to 37,5 km a day.

It is worth noting that the former legions were always accompanied by rolling stock. These mobile camps moved with the army. Along with the camp, military supplies and equipment were transported on the rolling stock, along with the rolling stock that also repaired military equipment, repair workshops, and food. Those were particularly easy to be attacked by enemies because the army was very flexible.

After Marius’ reform, his soldiers were called “Marius’ mules”, because they had to wear all their equipment on the back. Marius’ idea was to limit the number of rolling stock (impedimenta). From now on, the legionary was to carry tools for earthworks (including a sickle, wicker basket for carrying soil, pickaxe (dolabra) with a case, a tool for cutting peat), cooking utensils (made of bronze pot and cauldron), two wooden piles (pila muralia), rolled blanket, coat and ration of grain and rusks for 3 or more days. The whole, together with armour and weaponry, weighed from 33 to 44 kilos according to various sources.

Increasing the legionary’s equipment made it possible to reduce the rolling stock behind the army, thus transforming the army into a more mobile and organizationally efficient unit. It should be mentioned, however, that it was still packed with animals that determined the rhythm of the march (about 5 km/h). Each team (contubernium) with 8 soldiers had 1 mule who carried heavier items such as the team’s leather tent and burrs.


The so-called Marius reforms were aimed at improving the Roman army, which had low morale after the early defeats to the barbaric Teutons and Cimbrii. Gaius Marius did not intend to modernize the entire Roman army. It’s best to present this moment with a message from Plutarch:

For the Barbarians had a reflux, as it were, in their course, and streamed first into Spain. This gave Marius time to exercise the bodies of his men, to raise their spirits to a sturdier courage, and, what was the most important of all, to let them find out what sort of a man he was. For his sternness in the exercise of authority and his inflexibility in the infliction of punishment appeared to them, when they became accustomed to obedience and good behaviour, salutary as well as just, and they regarded the fierceness of his temper, the harshness of his voice, and that ferocity of his countenance which gradually became familiar, as fearful to their enemies rather than to themselves. But it was above all things the uprightness of his judicial decisions that pleased the soldiers; and of this the following illustration is given.

Plutarch from Cheronea, Marius, 14

Using his knowledge, experience and certain innovations, he created an efficient army. The army was to be strong, disciplined and universal, ready to act in various conditions, which, as it turned out, was achieved.

Roman legionaries during the march during the Second Dacian War. Legionaries carry all their belongings on their backs.
Author: Radu Oltean

Gaius Marius made a number of decisions to properly prepare his legions at the start. Most of them were not innovative, but the effectiveness of his troops and huge victories over Teutons in 102 BCE under Aquae Sextiae, and a year later Cimbri at Vercellae led to the fact that many Roman commanders began to imitate him and to a large extent such a Roman army has become a standard. Gaius Marius received the triumph for his victories together with Quintus Lutatius Catulus, the second consul of 102 BCE.

Despite the averting danger from the Germans, Marius’ reforms were to have a negative effect in the future. The lack of security for veterans in old age combined with long-term service (initially 16 years) meant that the commanders began to feel a specific responsibility towards demobilized soldiers. In the future, each of the leaders (including Marius himself) will strive to give land to his legionaries, which will result in their strong personal relationship with the army and veterans. Instead, they will be able to weigh everything and follow their commander against everyone, even Rome, for the spoils and spoil.

  1. In practice, however, we can speak of such an army only during the reign of Octavian Augustus, when the pay was regularly paid and allowed to support his family. The pay of 5 aces a day was simply too small for the soldiers to support themselves. At that time, they were hoping for war spoils. If the chief gave his pupils gains, they were later grateful to him. As a result, the loyalty of the legionnaires was more and more the responsibility of the commander, not the state. Hence the subsequent increase in the power of individual politicians and civil wars in the first century BCE.
  2. It is worth mentioning that the minimum property census, determining whether a citizen will arm in the event of a war and will take part in it, has been regularly reduced: 11,000 aces before the Second Punic War; 4,000 for the clash with Hannibal; in the years 130-120 BCE reaching only 1500 aces. So here you can see Rome's efforts to attract recruits.
  3. The number of the legion has changed over the centuries and rather resulted from the need of the moment. The Romans were extremely flexible here.
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