Roman Legion

The Roman legion (from Latin legio, legionis, f., from lego, legere, legi, lectus — to collect) was the basic military unit of the ancient Roman army. It consisted of a core of heavy infantry (legionaries), with auxiliary cavalry and ranged troops, typically skirmishers. The size of a typical legion varied widely throughout the history of ancient Rome , with complements ranging from 5000-6000 men in the republican period of Rome, to the fairly standard number of around 5,400 in the early and middle imperial period and finally to on average 1000-2000 men in the very late imperial period. As legions were not standing armies until the Marian reforms (c. 107 BC), and were instead created, used, and disbanded again, several hundred Legions were named and numbered throughout Roman history. To date, about 50 have been identified. In the time of the Early Roman Empire, there were usually about 28 standing Legions plus their Auxiliaries, with more raised as needed.

Due to the enormous military successes of the Roman Republic and the Roman Empire the legion has long been regarded as the prime ancient model for military efficiency and ability.

Originally, in the time of the Kings, the legio ("conscription") was the whole Roman army, composed of levied citizens. Much of Roman history of this era is founded on legends, but it is believed that during the reign of Servius Tullius, all Roman able-bodied, property-owning male citizens were first divided into five classes for military service based on wealth, since soldiers provided their own weapons and equipment.

• Legio V Macedonica
  
  Legio V Macedonica ("Macedonian") was a Roman legion. It was probably originally levied by consul Gaius Vibius Pansa Caetronianus and Octavian in 43 BC, and it existed in Moesia at least until 5th century. Its symbol was the bull, but the eagle was used as well. The cognomen Macedonica comes from the fact that the legion was stationed in Macedonia for a period of its life.
  

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