Shortly afterwards, Alexius Angelus, son of the deposed Byzantine emperor Isaac II, arrived in Zara, looking for help to overthrow his uncle, Alexius III, after he violently seized the throne from Isaac. Dandolo agreed to the Crusade leaders' plan to place Alexius Angelus on the throne of the Byzantine Empire in return for his support and funds to help the Crusade. The Crusaders thus took another detour to Constantinople, where the conquest and sack of Constantinople took place on 12 April 1204. During the looting, Dandolo had many items of value sent back to Venice, including the four Horses of St. Mark that decorate the Venetian cathedral to this day. When Constantinople fell, Dandolo understood that he needed to quickly restore stability to the empire to avoid disorder that could threaten Venice. One necessary task was to find an emperor for the new Latin empire. Dandolo was offered the position, but he refused, and Baldwin of Flanders instead took the throne.