In the Roman Empire, the legion was the most famous and powerful military unit the Romans had. It would be comprised of 5,300 to 6,000 men, depending whether the legion had non-combantants attached. The Legion was made up of 10 cohorts, which would be made up of 6 centuries, in which each century would actually be made up of 80 men, not 100. In battle, the strongest and weakest cohorts would be mixed in a particular order to provide experience for the newest soldiers and enough power to win over an enemy. The Legion was essentially a slaughtering machine. It would be completely made up of men with heavy shields and armor, a Gladius (sword), one Pilum (javelin), and one Pugio (dagger). A legion would throw its PIlum before charging into enemies. The Pilum was specially created in which once thrown, it could not be thrown again.
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The Roman Empire 