Byzantine emperor (January-April 1204); the last ruler of the empire before the conquest of Constantinople by the Fourth Crusade (1202-1204).
A scion of the noble Doukas family, Alexios was nicknamed Mourtzouphlos (Gr. “bushy-browed,” “sullen,” “morose”) and joined the abortive coup (1200/1201) of John Axouchos Komnenos against Alexios III Angelos, for which he was incarcerated until July 1203, when Isaac II and Alexios IV were jointly brought to the throne with crusader help. On his release, Mourtzouphlos was given the title of protovestiarios, which did not, however, prevent him from manifesting his anti-Latin feelings, thus undermining the pro-Latin policies of Alexios IV. On 27 January 1204, Byzantine popular discontent against Alexios IV resulted in the brief proclamation of the unwilling Nicholas Kanabos as emperor, a development exploited by Mourtzouphlos, who encouraged Alexios IV to seek crusader aid to oust Kana- bos and then used this as a pretext to overthrow him (28/29 January 1204).
After being crowned (5 February), Mourtzouphlos tried to fortify parts of his capital and dictate demands for an immediate crusader withdrawal, which soon provoked an attack. He and his supporters repelled a first crusader assault (9 February) but were eventually overwhelmed, and he fled just before Constantinople was stormed and captured (12/13 April). During the summer of 1204 Mourtzouphlos sought refuge at Mosynopolis in Thrace with Alexios III, who gave him in marriage his daughter Eudokia Angelina; however, Alexios III had evidently not forgiven his new son-in-law’s previous plots against him, and had him blinded (August 1204). Mourtzouphlos ended up in the hands of the Franks, who had him tried and found guilty of treason against Alexios IV; he was cast to his death from the heights of the Theo- dosian Column in Constantinople.