The first securely identifiable holder of the office was
Eusebius under Emperor
Constantius II (), but the position may have been introduced already under
Constantine the Great (), in replacement of the older
a cubiculo. He controlled the corps of the
cubicularii (κουβικουλάριοι, ), 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. During the 4th-5th centuries, the
praepositus gained in power: in the late 4th century, he gained control over the imperial estates of
Cappadocia (the
domus divina per Cappadociam of the
Notitia), and was elevated in rank to
vir illustris and the equivalent of
quaestor. A separate
praepositus was also established for the household of the Byzantine empress (
praepositus Augustae), with a similar structure of subordinate officials. In the
Western Roman Empire, the post continued in existence until its fall, and was also used in the court of the
Ostrogoth king Theodoric the Great, where it was held by a
Goth, Triwila. In the mid-6th century, however, the supervision of the Cappadocian estates was entrusted to a separate official in charge of the imperial patrimony, and its authority declined. In the 7th-8th centuries, paralleling changes in many other administrative offices, the position of
praepositus, or
praipositos in Greek, was much reduced in power, as parts of his
officium were split off. The
cubicularii of the bedchamber (distinguished as , in Greek) were separated under the
parakoimōmenos, while the imperial wardrobe (, , ) under its head, the
prōtovestiarios, was also made into a separate department. The
praipositos continued to supervise the remainder of the
koubikoularioi, with the
primikērios tou kouboukleiou as his chief aide. He retained a considerable role in court ceremonies, and ranked in the higher class of the
patrikioi. According to
Constantine VII (), the
praipositos, together with the
prōtomagistros and the
eparch of Constantinople used to form a
regency in the emperor's absence. The continuing actual office of
praipositos, however, is not to be confused with the dignity (, ) of the same name, which was a court rank created in the 7th or 8th century and restricted to eunuchs. According to Philotheos's
Klētorologion of 899, it ranked below the dignity of
patrikios and above that of
prōtospatharios, and the insignia (
brabeion) of the office were
ivory tablets. The title is last attested in 1087. ==Notable
praepositi==