Roman Army" is the name given by English-speakers to the soldiers and other military forces who served the Roman Kingdom, the Roman Republic and later the Roman Empire. The Roman words for the military in general were based on the word for one soldier, miles. The army in general was the militia, and a commander of military operations, militiae magister. In the republic, a general might be called imperator, "commander" (as in Caesar imperator), but under the empire, that term became reserved for the highest office.