The
Roman army (
Latin: , literally:
Roman Army;
Ancient Greek: , transcription:
stratos Romaion) is a term encompassing the terrestrial armed forces deployed by the
Roman Kingdom (to c. 500 BC), the
Roman Republic (500–31 BC), the
Roman Empire (31 BC – 395/476 AD) and its successor the
East Roman or Byzantine Empire. It is thus a term that spans approximately 2,000 years, during which the Roman armed forces underwent numerous permutations in composition, organization, equipment and tactics, while conserving a core of lasting traditions.