Constantine Angelos Doukas

Constantine Angelos Doukas, Latinized as Constantine Angelus Ducas (Κωνσταντίνος Άγγελος Δούκας, Kōnstantinos Angelos Doukas), was a usurper who attempted to overthrow Byzantine emperor Isaac II Angelos in 1193.

Career
Constantine Angelos Doukas was the cousin of emperor Isaac II Angelos, and he was entrusted by the emperor with the Bulgarian War against the Vlach (1185–1197) during its later stages. Although he was still a young man and quite impetuous, he quickly turned around a situation that had been growing steadily worse for the empire. Training his troops to obey him without question, his native aggression saw the Vlach insurgents fear his approaches. His exuberance was at first kept in check by his military advisors, but a string of successes over Peter IV of Bulgaria went to his head and he declared himself emperor over their objections. He marched towards Adrianople but was imprisoned by his former comrades-in-arms who handed Constantine over to Isaac. Isaac II blinded him, and Constantine's absence saw the Second Bulgarian Empire once again gain the upper hand in the war against the Byzantine Empire.