Foederati
Foederati ( FED-ə-RAY-ty; singular: foederatus FED-ə-RAY-təs) were peoples and cities bound by a treaty, known as foedus, with Rome. During the Roman Republic, the term identified the socii, but during the Roman Empire, it was used to describe foreign states, client kingdoms or barbarian tribes to which the empire provided benefits in exchange for military assistance.