In the 5th century BC, the Roman Army was far from being the powerful and efficient fighting machine it would become a couple of centuries later. However, after the disastrous defeat at the hands of the Gauls at the Battle of Gallia in 390 BC, during the Gallic sack of Rome, it would be completely reorganized. Up until then, the Roman legion had been composed of only 3,000 foot soldiers; after the reorganization, it was increased to 6,000 heavy infantry men and 2,400 light infantry as hours of training was also increased.
In 366 BC, the Roman Army annual draft was split between two Consuls, each commanding a legion composed of 4,500 soldiers. During the Samnite Wars, this annual draft would be doubled to four legions, two for each Consuls. This increase in size was possible because the growth of the Roman population, with the legion still comprising lines of heavily and lines of lightly-armed soldiers. The lightly-armed soldiers lacked adequate protective gear as they, along with the skirmishers (velites), were drawn from the poorer classes.
By the 3rd century BC, the armament of the Roman Army had become uniform. All the heavily armed soldiers were equipped with gladius, which was a sword with short and pointed straight blade, two javelins, a scutum, which was a large rectangular shield, chain mail, and a bronze helmet. The sons of senators and of a growing number of wealthy citizens served in the cavalry.
Formation
The Roman Army learned their effective field deployment and organization from the Samnites; it was called the maniple. It was a rectangular formation pattern containing 120 men, who were arranged in three 40-men lines. Thus, a legion was made up of several maniples. This new formation resulted in greater flexibility in the battlefield. Up until the end of the Punic Wars, the legionary or soldier was free Roman citizen drafted into the army in time of war.
In 107 BC, however, Gaius Marius, a Roman Consul, carried out an extensive military reforms of the Roman Army. He created a new rectangular formation called the cohort, which was composed of 500 men. He rearranged the maniple, reducing their number to 100 and redeploying them in a long 100-men row, or line, which he called century. Then he put five centuries together to form one solid cohort, with each one of the centuries under the command of a centurion. The word “century” derives from Latin “centuria”, which means “one hundred”. Thus, a century was made up of 100 men, and not 80.
Therefore, ten cohorts made up a 5,000-men legion, and the Roman Army was composed of several legions. The Roman weapons and equipment were standardized as every soldier had exactly the same type of weapons, which were provided by the government and they were paid and had the right to a portion of the spoils of war. With the reforms implemented by Gaius Marius, a poor citizen was well-armed, with a gladius, a pugio (dagger), a pilum (javelin), chain mail, a bronze helmet, and a scutum.
Roman Army legionaries in France
Below, a relief in stone of two Roman legionaries holding their scutum (shield), and wearing the helmet and chain mail.
