Marian Reforms (107 BC): How Gaius Marius Changed the Legion

The Marian reforms are the changes to the Roman army associated with Gaius Marius, consul in 107 BC and five times consul from 104 to 100 BC. The best attested is his decision to enlist poor, landless volunteers for the war against Jugurtha in North Africa. Ancient and modern writers have credited him with much more, but historians now argue that the “reforms” were part of a longer, gradual transformation of the legion.

Background: a militia of property owners

In the early and middle Republic, the Roman legion was a citizen militia. Men served when called up, and only those with a minimum amount of property, registered in the census, were eligible. They bought their own equipment, which varied with wealth: the poorest served as light-armed velites, the richest as cavalry.

Over the 2nd century BC the property threshold seems to have dropped. Figures given by ancient authors suggest a fall from 11,000 asses to 4,000 and then to 1,500, though their dating is uncertain. Long wars overseas made service a burden, and Roman commanders complained of difficulties in raising troops. The Gracchi reforms were partly an attempt to create more property-owning citizens fit for service.

Marius and the 107 BC levy

Marius, a “new man” from Arpinum, was elected consul for 107 BC and given the command in the Jugurthine War. The Senate allowed him to raise reinforcements but expected the recruitment to make him unpopular.

According to Sallust, Marius enlisted volunteers rather than relying only on the usual levy, and took most of them from the capite censi, citizens “counted by head” because they had little or no property. Sallust suggests two motives: a lack of suitable men, or Marius’s wish to build a following among people who owed everything to him.

This was not a change in law. Marius did not abolish the property qualification, and conscription continued to be used for decades. But the precedent of accepting the poor as volunteers was important, and many later armies were raised in a similar way.

Changes attributed to Marius

Several other innovations are linked to Marius, especially during his preparations against the Cimbri and Teutones from 104 BC:

• The eagle standard. Pliny the Elder says that in his second consulship (104 BC) Marius made the silver eagle, the aquila, the sole standard of the legion, replacing the wolf, minotaur, horse and boar.
• Marius’s mules. Plutarch reports that he made soldiers carry their own kit, rations and tools on a forked pole, so armies needed fewer baggage animals. Soldiers became known as muli Mariani.
• The pilum. Before the Battle of Vercellae in 101 BC, Plutarch says, Marius changed the javelin so that one of its two metal rivets was replaced by a wooden pin, making the head bend on impact so enemies could not throw it back.
• Training. Publius Rutilius Rufus, consul in 105 BC, introduced weapons drill modelled on the methods of gladiator trainers, and Marius adopted his trained troops.

What historians debate

Older textbooks often presented a single “Marian reform” that turned a citizen militia into a professional army in one stroke, abolished the velites and cavalry, and introduced the cohort of about 480 men as the main tactical unit. Modern scholarship is more cautious.

The cohort, a group of three maniples, was already used in the Second Punic War, according to Polybius, and replaced the old manipular formation gradually. The disappearance of citizen cavalry and velites is poorly documented and probably happened over several decades, with allied and foreign troops taking over those roles.

Even the importance of the 107 BC levy is debated. Some historians, following Emilio Gabba, see the steady lowering of the property qualification as the real change. Others, such as François Cadiou, argue that the idea of armies of landless proletarians in the late Republic is largely a modern construction.

What seems clear is that by the time of Julius Caesar the legion was more standardised, better trained and serving for longer periods than in the 3rd century BC, and that Marius’s commands contributed to this.

Key people

Gaius Marius (c. 157-86 BC) came from an equestrian family of Arpinum, south-east of Rome, and rose through military service, including at Numantia under Scipio Aemilianus. He married Julia, an aunt of Julius Caesar, which linked him to an old patrician family. His reputation as a soldier’s general, sharing hardships with his men, was central to his political success.

Publius Rutilius Rufus (c. 158-after 78 BC), a Stoic and a respected jurist, served as a legate in Numidia and became consul in 105 BC. His training methods produced the troops Marius later took over. He was later convicted in a notorious trial for extortion in Asia, widely believed to be unjust, and spent his last years in exile.

Lucius Appuleius Saturninus (died 100 BC), tribune in 103 and 100 BC, worked with Marius to secure land for veterans. His violent tactics led the Senate to pass its emergency decree against him in 100 BC; Marius, as consul, had to suppress him, and Saturninus was killed by a mob.

Myths and facts

Myth: Marius created a fully professional standing army. In fact, Roman armies were still raised for particular wars, conscription continued, and a permanent standing army with fixed terms and pensions came only under Augustus.

Myth: Marius gave all soldiers equipment paid for by the state. Ancient sources do not say this. Deductions for equipment from soldiers’ pay are recorded earlier, and state supply grew over time rather than being introduced by Marius.

Veterans, land and loyalty

Soldiers recruited from the poor needed something to live on after discharge. In 103 and 100 BC the tribune Lucius Appuleius Saturninus, an ally of Marius, passed or proposed laws granting land to Marius’s veterans in Africa and elsewhere. The state had no regular pension system, so generals had to fight political battles to reward their men.

This created a strong bond between commanders and soldiers. In 88 BC Sulla’s legions followed him in Sulla’s March on Rome, and later armies followed Pompey, Caesar and Octavian in civil wars. Historians still disagree over how far Marius’s own changes caused this, but the link between landless soldiers and political generals is widely accepted.

By the numbers

Timeline

• 2nd century BC: The property qualification for legionary service is lowered in stages.
• 107 BC: Marius, consul, enlists volunteers from the capite censi for the war against Jugurtha.
• 105 BC: Consul Publius Rutilius Rufus introduces new weapons drill.
• 104 BC: Marius, consul again, prepares an army against the Cimbri; the eagle becomes the sole legionary standard.
• 102 BC: Marius defeats the Teutones and Ambrones at Aquae Sextiae.
• 101 BC: Marius and Catulus destroy the Cimbri at Vercellae.
• 100 BC: Saturninus’s laws seek land for Marius’s veterans.

Why it matters

Whether or not they were a deliberate programme, the changes linked to Marius mark the shift from a part-time citizen army to the long-serving legions of the late Republic and Empire. They also helped create armies whose loyalty could be turned against Rome itself, one of the main reasons the Republic fell.