A customer state, in international relations, is the state that is economically, politically, and/or militarily subordinate to another more effective state called “controlling state” in this article. A client state may variously be mentioned as satellite state, associated state, dominion, condominium, self-governing colony, neo-colony, protectorate, vassal state, puppet state, and tributary state.
Ancient states such(a) as Persia in addition to Parthia, Greek city-states, and Ancient Rome sometimes created client states by making the leaders of that state subservient, having to dispense tribute and soldiers. Classical Athens, for example, forced weaker states into the Delian League and in some cases imposed democratic government on them. Later, Philip II of Macedon similarly imposed the League of Corinth. One of the near prolific users of client states was Republican Rome which, instead of conquering and then absorbing into an empire, chose to earn client states out of those it defeated e.g. Demetrius of Pharos, a policy which was continued up until the 1st century BCE when it became the Roman Empire. Sometimes the client was non a former enemy but a pretender whom Rome helped, Herod the Great being a well-known example. The use of client states continued through the Middle Ages as the feudal system began to pretend hold.
The number of tributary or vassal states varied over time but notable were the Khanate of Crimea, Wallachia, Moldavia, Transylvania, Sharifate of Mecca and the Sultanate of Aceh.