Ancient Rome was one of the greatest country and empire that have been ever existed in the history. Started as the small village in Italy it became the biggest and most powerful Empire of antiquity. Borders of the Roman Empire stretching from the deserts of Africa on the South to the Northern England and from Spain on the West to Euphrates on the East. However, it would be all impossible without Roman army, which conquered dozens of nations and brought a glory to Rome. Roman army was in war campaigns all the time. Thus, it was the most experienced army in antiquity.
Roman army almost the entire period of its existence was the most advanced among the ancient nations of the world. It started as the militia and through the years became a professional regular army with infantry and cavalry, with numerous auxiliary units and allied units. In Roman army the main fighting force has always been infantry. The main advantages of the Roman army were discipline, mobility, flexibility and tactical skills, allowing it to operate in a different terrain and harsh weather conditions.
In the days of the early Republic legion consisted legion consisted of 4,200 infantry and 300 cavalry. This army was not yet professional. Warrior served in the army only when it was necessary. Warrior himself had to provide himself with equipment, which led to a wide variety of weapons and armor.
Roman legion at that period based not only on a property qualification, but on the basis of different ages. The youngest and poorest soldiers were supposed to be armed with a sword, 6 darts, bows and arrows with the stock sling for throwing stones. This light infantry was called "velites" and used as skirmishers. These soldiers had no armor or helmet and were protected only by light shield. First time velites recruited separately from the legion.
Next by age and economic status group of soldiers was called hastati .They were armed with a sword, heavy (Gast) and light throwing (Pilum) spears and full protective arms. The third group is the principes –it were the heavy spearmen that were armed as well as hastati but had already experienced fighters. In the battle they placed behind the rows of hastati-to be able to help to younger warriors. The oldest and experienced in combat veterans were called triarii – they had instead of pilum a long spear. In combat, they placed in the third row, behind the principes and was the last reserve of legion.
In the first half of III century BC was a new reorganization of the Roman army. First was introduced uniform for maniples. Previously, each maniple consisted of hastati, principes and triarii, now it manned by only one of these types of infantry. Maniples ceased to be mixed and become specialized. In addition to the number of maniples in legion rose from 10 to 30. Legion now consisted of 30 maniples (10 hastati, 10 principes and 10 triarii). In the first two groups, the structure was the same -up to 120 heavy infantry and 40 velites. In Triarii maniple number of infantry was 60 triarii and 40 velites. Each maniple consisted of two centuriae, but they had no independent significance, because of the smallest tactical unit remained maniple. Three hundred cavalry of legion were divided into ten turma, 30 people each. The horsemen were armed by the Greek pattern: armor, round shield and spear. Each cavalry turma had three decurion - "foreman" and three selected guard – optiones. First decurion commanded the turma. Thus, in legion were 4,500 people, including 1,200 velites and 300 riders.
However, during the second Punic War it is evident that the military system of Rome is far from ideal. Despite the fact that military service is paid, wages are basically went to operating costs.
In 107 B.C. Marius was elected consul, who focused all his attention on strengthening the Roman army. He provided access to the legions to all volunteers who had Roman citizenship, regardless of their property. Capite censi-the poorest people of Roma have flooded the legions. These people are not eager to get rid of soldiers of life - on the contrary, they were willing to serve all life. Many people were able to make a career from simple soldier to centurion.
In the old system legions were formed anew in each campaign, thus they lacked a sense of cohesion. However the Gaius Marius reform has changed this situation. Each legion got its flag- the famous Roman eagle "Aquila", which became a symbol of victory and power for many centuries.
Around the same time radically changed structure of the Legion. During the Second Punic War in the formation of the legions due to lack of manpower Romans canceled the age principle of separation in hastati, principes and Triarii. Now, all the soldiers were armed with a sword and pilum and were defended by one type of armor. Maniple lost its former tactical value and was increased up to 120 legioners and combined into a cohort where were three maniples. Tactical unit became the cohort. Thus, the legion became consist of ten cohorts. Separation on centuries preserved as rank of centurion, and in the camps and forts soldiers were still housed in centuria.
Military commanders changed significantly throughout the Roman history. At the time of the monarchy, the hoplites army was guided by kings of Rome. In the early and middle Roman Republic, military forces were under the command of one or the two consuls, who were elected annually. During the late Republic, representatives of the Roman Senatorial elite, as elected members of the traditional social institutions, known as the cursus honorum, primarily quaestors (often appointed deputy field commanders), then - as praetors.
After the end of the term of office as praetor or consul, a senator could be appointed by the Senate propretor or proconsul to manage one of the provinces. Junior officers (up to the level of centurion) were appointed by their commanders from among their subordinates or from the recommended by political allies representatives of senatorial elite. From the time of Augustus, whose most important political priority was to take an army under constant and sole control, the Emperor was the legal commander of each legion but commanded through legate (Latin legatus), whom he appointed from the Senatorial elite. In the province, where was only one legion, the legate commanded the legion (legatus legionis) and served as governor of the province, while in the province with more than one legion, each legion was guided by the legate. Legates were guided by the governor of the province (or legate of higher level). During the last stages of the imperial era, this model was canceled. Governors were deprived of military power and command of the army group was transferred to the provincial generals (Latin duces), appointed by the emperor. These were not the representatives of the Roman elite and the people who climbed the ranks and had a working knowledge of warfare. Increasingly, people have tried (often successfully) to usurp the power of the emperor, who appointed them. Reduced resources, increasing political chaos and civil war eventually made the Empire vulnerable to attack and acquisitions neighboring barbarian tribes.
Goldsworthy, Adrian. The Complete Roman Army. London: Thames & Hudson, 2011.
McNab, Chris. The Roman Army: The Greatest War Machine of the Ancient World. Oxford: Osprey Publishing, 2010.