Primicerius

The Latin term primicerius, hellenized as primikērios (Greek: πριμικήριος), was a title applied in the later Roman Empire and the Byzantine Empire to the heads of administrative departments, and also used by the Church to denote the heads of various colleges.

Etymologically the term derives from primus in cera, which is to say in tabula cerata, the first name in a list of a class of officials, which was usually inscribed on a waxed tablet.

From their origin in the court of the Dominate, there were several primicerii (primikērioi in Greek, from the 12th century usually spelled primmikērioi). In the court, there was the primicerius sacri cubiculi (in Byzantine times the primikērios of the kouboukleion), in charge of the emperor's bedchamber, almost always a eunuch. The title was also given to court officials in combination with other offices connected to the imperial person, such as the special treasury (eidikon) or the imperial wardrobe (vestiarion). Other primicerii headed some of the scrinia (departments) of the palace, chiefly the notarii (notarioi or taboularioi in Byzantine sources).

In the Late Roman army, the primicerius was a rank junior to the tribunus and senior to the senator. They are best attested in units associated with the imperial court, chiefly imperial guards. Thus in the 4th to 6th centuries there were the primicerii of the protectores domestici and of the Scholae Palatinae, but also primicerii in charge of the armament factories (fabricae), which, like the Scholae, where under the jurisdiction of the magister officiorum.Primicerii are also to be found in the staffs of regional military commanders (duces), as well as in some regular military units. In the later Byzantine era, under the Komnenian emperors, primikērioi appear as commanders in the palace regiments of the Manglabitai, Vardariōtai, Vestiaritai and the Varangians.

...
Wikipedia