Praepositus sacri cubiculi

The praepositus sacri cubiculi ("provost of the sacred bedchamber", in Greek: πραιπόσιτος τοῦ εὐσεβεστάτου κοιτῶνος) was one of the senior palace offices in the late Roman Empire. Its holder was usually a eunuch, and acted as the grand chamberlain of the palace, wielding considerable authority and influence. In the 7th or 8th century, the title was also given to an for eunuch palace servants. The title and office continued in use in the Byzantine Empire until the late 11th century.

The first securely identifiable holder of the office was Eusebius under Emperor Constantius II (r. 337–361), but the position may have been introduced already under Emperor Constantine I (r. 306–337), in replacement of the older a cubiculo. He controlled the corps of the cubicularii (Greek: κουβικουλάριοι, koubikoularioi), also eunuchs, and was responsible for the imperial bedchamber, wardrobe and receptions. Originally under the control of the castrensis sacri palatii, he soon became directly subordinated to the Byzantine emperor. His proximity to the Byzantine emperor gave him great power, and several praepositi wielded considerable influence in the governance of the Byzantine Empire. In the Notitia Dignitatum, the praepositus is listed immediately after the praetorian prefects, the urban prefect and the magistri militum. However, due to the loss of the relevant pages of the Notitia, we do not know the structure of his officium. Senior assistants were the primicerius sacri cubiculi and the comes sacrae vestis.

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