ALEXIUS V., eastern Roman emperor, was proclaimed emperor on the 5th of February 1204, during the siege of Constantinople by the Latins (Fourth Crusade). His name was Alexius Ducas Murtzuphlos, and he was a connexion of the imperial house of the Angeli. His elevation was the result of a revolution in the city against Isaac II. and Alexius IV. He conducted the defence with great bravery till it became hopeless (April 12), whereupon he fled. He would then have made common cause with Alexius III. against the Latins, but was blinded by that ex-monarch and fell into the hands of the crusaders, who put him to death by casting him from the top of the Pillar of Theodosius as the murderer of Alexius IV.