Roman Army

The Roman army (Latin: exercitus Romanus) is a term that can in general be applied to the terrestrial armed forces deployed by the Romans throughout the duration of Ancient Rome, from the Roman Kingdom (to c. 500 BC) to the Roman Republic (500–31 BC) and the Roman Empire (31 BC – 395/476 AD), and its successor the East Roman or Byzantine Empire. It is thus a term that may span approximately 2,000 years, during which the Roman armed forces underwent numerous permutations in composition, organisation, equipment and tactics, while conserving a core of lasting traditions.

The Early Roman army of the Roman Kingdom and of the early Republic (to c. 300 BC). During this period, when warfare chiefly consisted of small-scale plundering raids, it has been suggested that the Roman Army followed Etruscan or Greek models of organisation and equipment. The early Roman army was based on an annual levy.

The infantry ranks were filled with the lower classes while the cavalry (equites or celeres) were left to the patricians, because the wealthier could afford horses. Moreover, the commanding authority during the regal period was the high king. Until the establishment of the Republic and the office of consul, the king assumed the role of commander-in-chief. However, from about 508 BC Rome no longer had a king. The commanding position of the army was given to the consuls, "who were charged both singly and jointly to take care to preserve the Republic from danger".

The term legion is derived from the Latin word legio; which ultimately means draft or levy. At first there were only four legions. These legions were numbered "I" to "IIII", with the fourth being written as such and not "IV". The first legion was seen as the most prestigious. The latter being a recurring theme in many elements of the Roman army. The bulk of the army was made up of citizens. These citizens could not choose the legion to which they were allocated. Any man "from ages 16-46 were selected by ballot" and assigned to a legion.

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