Theodore Kastamonites (Greek: Θεόδωρος Κασταμονίτης) was a Byzantine aristocrat and the all-powerful chief minister for most of the first reign of his nephew, Emperor Isaac II Angelos.
The Kastamonites family probably hailed from Kastamon in Paphlagonia, and had emerged in the late 11th century as one of the Byzantine Empire's aristocratic clans, its members holding various civil and military offices under the Komnenian emperors.
[3] Although suffering from gout so that he had to be carried about in a litter, according to his contemporary Niketas Choniates, Kastamonites was a capable official, particularly in taxation matters—the Pisan and Genoese merchants in particular complained that he always exacted full customs duties from them—and an eloquent speaker.
Indeed, Kastamonites became the de facto ruler of the empire, as he handled all government affairs, and his nephew always acceded to his requests.
[7] Nevertheless, on 15 August 1193, during the procession of the Dormition of the Theotokos, Kastamonites was hailed by the crowd as lord and emperor; hearing that, he was stricken by apoplexy, and although he briefly recovered, he died a few days later.