Protostrator

Prōtostratōr (Greek: πρωτοστράτωρ) was a Byzantine , originating as the imperial stable master. Its proximity to the imperial person led to a highly visible role in imperial ceremonies, and served as a springboard for several capable individuals, like Manuel the Armenian or the future emperors Michael II and Basil I the Macedonian, to reach the highest offices. From the mid-11th century, the post rose in importance, becoming more an honorific dignity for senior members of the court, than an actual office. From the 13th century on, the post could be held by several persons, and ranked eighth in the overall hierarchy of the court. Throughout its history, it was a title often borne by senior military commanders. The female form of the title, given to the wives of the prōtostratores, was prōtostratorissa (πρωτοστρατόρισσα).

The title means "first stratōr", reflecting the office's initial nature as chief of the imperial order (taxis) of the stratores (στράτορες, "grooms"), who formed a schola stratorum, as attested for staff of the praetorian prefect of Africa in the 6th century. A domestikos tōn stratorōn appears under Justinian II (reigned 685–695, 705–711) and a prōtostratōr of the Opsikion named Rouphos in 712. The first holder of the post to be mentioned as a relatively important personage, however, is the spatharios Constantine, son of the patrikios Bardanes, mentioned near the bottom of a list of victims of iconoclast persecution under Constantine V (r. 741–775) in 765. The spatharios Constantine is also the first known holder of the post of "imperial prōtostratōr" (βασιλικός πρωτοστράτωρ, basilikos prōtostratōr).

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