The term ‘client kings’ denotes a range of monarchs and quasi‐monarchs of non‐Roman peoples who enjoyed a relationship with Rome that was essentially harmonious but unequal. These were rulers under the patronage of the Roman state, but the less abrasive language of friendship (see amicitia) was the norm. The Roman state called such kings ‘king and ally and friend’, in a formal recognition by the senate. Grand ceremony seems often to have accompanied such recognitions, under republic and Principate alike.
From the 3rd cent. bc at the latest Rome developed such relationships with a view to consolidating or expanding her empire in Italy and beyond. Hieron 2 II of Syracuse is often regarded as the first client king (c.263 bc), but he doubtless had predecessors. And Rome continued to build and maintain relationships with client kings throughout her history. Many kingdoms did indeed become provincial territory over the centuries, usually when Rome felt the need to step in to control local unrest: e.g. where kings failed to manage their succession, where a dynasty ended, or where local conditions had changed. See provincia, province.
Client kingdoms were usually located at the margins of Roman control, whether on the edge of the empire or in an area which Rome would find difficult and expensive to administer directly. At the frontier, client kingdoms were important reservoirs of manpower, resources, and local knowledge. Rome expected client kings to meet her demands whenever she saw fit to make them, but client kings were not required to pay regular taxes. In return, client kings expected Rome to ensure their positions locally. The nearest Roman legions forestalled the movements of client kings' enemies, both internal and external, by their very presence. Where necessary, Roman forces came to the aid of client kings, who might ultimately take refuge on Roman territory. On occasion, Rome might prefer to come to an arrangement with the enemies of her client kings, but it was the unspoken promise of Roman support that kept client kings loyal to Rome (or loyal enough). One expression of that expectation was the occasional bequest by client kings of their kingdoms to Rome where no other acceptable successor was available to them (e.g. Attalus III of Pergamum).
Client kings, like cities and others, exercised their relationship with Rome through more personal relations with leading individuals and families at Rome. Under the Principate such personal bonds continued to proliferate, but the emperor and his family now became the most attractive source of patronage for client kings, so that they became pre‐eminent in royal relations as in all else. Augustus seems deliberately to have made kings more a part of the Roman empire, following a trend set esp. by Caesar and Antony (Marcus Antonius ). Most client kings now held Roman citizenship: by ad 100 they had begun to enter the senate. They regularly sent their sons to grow up in Rome, preferably with the imperial family. Augustus is said to have encouraged marriages among client royalty. In their kingdoms, client kings named their cities after the emperor or members of his family: they also celebrated the imperial (ruler‐) cult, and a few kings were priests of that cult. The ruling emperor was depicted on royal coinage. Coercion was not required: the relationship between client king and Rome, however unequal, was based upon mutual advantage.
Subjects: Classical Studies.