Roman legion

The Roman legion (Latin: legiō, [ˈɫɛɡioː]) was the largest military unit of the Roman army, composed of 4,200 infantry and 300 equites (cavalry) in the period of the Roman Republic (509 BC–27 BC); and was composed of 5,200 infantry and 120 auxilia in the period of the Roman Empire (27 BC – AD 476).