Watch The Conquest of Constantinople Full Movie Free Online 123Movies. The Turkish Sultan decides to send his armies in war against the remnant of the Roman Empire, Byzantine. All of his advisory council assent to the move with the exception of one aged councilor, who allies himself with the Byzantines, who kidnap the fiancée of the Turkis army leader. The Sultan orders the army leader, along with two others, to proceed to Byzantine for espionage purposes. There, they contact a couple sympathetic to the Turkish cause and, with their home as the base, gather information about the city's defenses. The Byzantines capture the couple and two of the Turks, leaving only the army leader to escape with the vital information. The Turks use it to make an easy conquest, ending the Roman empire, and creating the Ottoman empire.