On the night of 24 July 1261, a group of soldiers under Alexios Strategopoulos managed to enter Constantinople through a secret passageway and captured the city. Baldwin was asleep in the Blachernae Palace when the noise of the fighting awoke him; upon seeing the Byzantine troops advance upon him, he fled in such haste that he left his crown and sceptre behind him. Baldwin made his way to the harbor where he boarded a Venetian galley to Negropont. From there he proceeded to Athens, thence to Apulia, finally to France. As titular emperor, his role was still the same, to beg help from the western powers. In 1267 he went to Italy; his hopes were centred on Charles of Anjou. Charles seriously entertained the idea of conquering Constantinople, though his efforts were destroyed during the Sicilian Vespers, an event perhaps engineered by Michael VIII Palaeologus of Constantinople. To this intent, he signed the Treaty of Viterbo with Baldwin (May 1267). During the next year Baldwin and his son Philip lived on pensions from Charles. In October 1273 Philip married Beatrice, daughter of Charles, at Foggia. A few days later Baldwin died in Naples. Under Baldwin II, Constantinople's population had fallen to a mere 35,000 people.