What was a Roman Legion?

Roman Legion Infantry Soldiers

Augustus, the first emperor of Rome had in his empire 25 legions of approximately 6,000 soldiers each. A legion was formed of 10 Cohorts (540 men in each Cohort). Each Cohort was subdivided into 6 Centuries (90 men formed a Century), and each legion had a wing of 120 cavalry.

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Roman Legions