caesar
In the Roman Empire the title of Caesar was given to the Emperor. From the reign of Diocletian (284-305) on this title was conferred on the young co-emperor. This was also the highest title on the hierarchy of the Byzantine court. In the 8th c. the title of Caesar was usually given to the successor of the throne. In the late 11th c. this office was downgraded and from the 14th c. on it was mainly conferred on foreign princes.

doukas (lat. dux)
Antiquity: Roman military commander who, in some provinces, combined military and civil functions.Buzantium: a higher military officer. From the second half of the 10th c. the title indicates the military comander of a larger district. After the 12th c., doukes were called the governors of small themes.

droungarios tou ploimou
("droungarios of the fleet") Commander of the byzantine fleet stationed Constantinople. Droungarios tou ploimou is first mentioned in the midle 9th C (Taktikon of Uspenski).

nobelissimos
A Byzantine high-ranking dignity that appeared in the Early Byzantine period. Until the first half of the 11th c., it was exclusively bestowed on members of the imperial family. The title survived until the Palaiologan era.

patrikios
(from lat. patricius) Higher title of honour, placed, according to the "Tactika" of the 9th and the 10th centuries, between anthypatos and protospatharios. It was given to the most important governors and generals. Gradually, however, it fell into disuse and from the 12th century did not exist any more.

praefectus urbi (prefect of the city)
(later referred to as the eparch of the city) Αdministrator and virtual governor of Constantinople in the Early/Middle Byzantine Era. He was responsible for the surveillance and the harmonius life of the Capital. One of his responsibilities was to control the commercial and manufacturing activities of Constantinople. After 1204, however, the office began to diminish, while from the 14th century, his responsibilities were assumed by two officers, the so-called kephalatikeuontai of the capital.

praepositos
(from lat. praepositus sacri cubiculi) The praepositos or praipositos (πραιπόσιτος του ιερού κουβουκλίου or του ευσεβεστάτου κοιτώνος) was a grand chamberlain by the Early Byzantine period the highest official, usually Eunuch, in the imperial service. After the 6th C. his functions were assumed by the parakoimomenos. The dignity involved in palace ceremony and disappeared until the end of 11th C.

protovestiarios
(and protovestiarites) Honorific title given to high-ranking officials and future emperors during this period. The protovestiarios was originally responsible for the imperial wardrobe, but in the 9th-11th centuries the holders of the title could command an army or conduct negotiations with foreign states.