Modern studies of Roman slave subownership have been heavily influenced by Erman’s seminal study on slave vicarii. Based on the etymology of the word vicarius, Erman argued that initially the main function of vicarii was to be substitutes of other slaves. Only in the late Republic did the word vicarius also start to denote a slave that was part of another slave’s peculium. This thesis challenges Erman’s dichotomist view of the historical evolution of the Roman vicariat by arguing that the semantics of the word vicarius was already fully developed in the earliest stages for which written records have survived, and that it remained unchanged during the whole central period of Roman history (212 BC-AD 235). There was always only one type of slave vicarius: a slave who was part of another slave’s peculium. The term used to denote this type of slave has little historical relevance, as their purpose was not to replace the slaves they were subordinated to in the service of the master. If they ever performed tasks in lieu of their superiors, it was a consequence of being subordinated to them as independently controlled property. Chapter One focuses on the semantics of the word vicarius in literary sources. It shows that the term had two different meanings depending on whether it was used in relation to free people or to slaves, and that the semantic and syntactic context made the two meanings always distinguishable. Chapter Two deals exclusively with legal sources. It argues that, in the writings of the jurists, a slave vicarius was always an asset of another slave’s peculium, regardless of the tasks they performed. Chapter Three focuses on epigraphic texts produced by slave vicarii themselves or by the people who were closely related to them. It shows how slaves used the title vicarius to mark their permanent personal relationship to another slave. It also discusses the criteria used by Erman and Weaver in their unsuccessful attempts to distinguish between different types of vicarii in the sources. Finally, a short postscript provides a concise description of the semantic change the word vicarius went through in the fourth century AD, and it assesses the possibility that slave subownership survived in late Antiquity even though no slave vicarii are attested sporting the title.

La figure du uicarius, esclave appartenant à un esclave en chef (ordinarius) dans le pécule duquel il se trouve, traduit une hiérarchisation à l’intérieur du microcosme de la sous-dépendance. Comme en témoignent les sources, à la fois multiples et diversifiées, le vicariat complexifie à l’évidence l’appréhension des stratifications serviles. Ce travail entreprend d’éclairer l’origine de ce statut (achat ou héritage cognatique). Ce faisant, il révèle une stratégie de parenté qui contribue à la consolidation et à la réinvention des logiques de la famille servile. Il éclaire par ailleurs l’utilité, tant domestique que professionnelle, du vicariat. Pépinière de jeunes esclaves, le vicariat est une « école servile ». En formant les vicaires à leur propre « métier d’esclave », les ordinarii, véritables magistri, leur dispensent un savoir spécialisé (peritia) de haute technicité. Véritables chevilles ouvrières de l’Empire, ils constituent dans la familia Caesaris, où ils sont massivement représentés, le socle de l’appareil d’Etat romain. / The vicariat was a subownership system based on a slave (uicarius) belonging to another slave (ordinarius). The uicarii were included in the peculium of the first-degree slaves. The vicariat testified of hierarchies among slaves. This study aims to enlight origin of this status (purchase or cognatic inheritance). By doing so, it disclosed strategies in order to strengthen the slaves families. It also demonstrates vicariat’s utility on the domestic level as well as professional. The vicariat was a nursury for young slaves and a “slave school”. By training uicarii for a specific work, the chief slaves were magistri who taught them specialized knowledges. In the familia Caesaris, the vicariat was a important linchpin of administration in Roman State.