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 Constantine the Great (r. 306–337), in replacement of the older a cubiculo.
[2] 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,[4] and its authority declined.
[2] 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.
[5] The continuing actual office of praipositos, however, is not to be confused with the dignity (διὰ βραβείου ἀξία, dia brabeiou axia) of the same name, which was a court rank created in the 7th or 8th century and restricted to eunuchs.