Subsequent despots were the sons of the Emperor Manuel II Palaiologos, brother of the despot Theodore: Theodore II, Constantine, Demetrios, and Thomas. As Latin power in the Peloponnese waned during the 15th century, the Despotate of the Morea expanded to incorporate the entire peninsula in 1430 with territory being acquired by dowry settlements, and the conquest of Patras by Constantine. However, in 1446 the Ottoman Sultan Murad II destroyed the Byzantine defences—the Hexamilion wall at the Isthmus of Corinth. His attack opened the peninsula to invasion, though Murad died before he could exploit this. His successor Mehmed II "the Conqueror" captured the Byzantine capital Constantinople in 1453. The despots, Demetrios Palaiologos and Thomas Palaiologos, brothers of the last emperor, failed to send him any aid, as Morea was recovering from a recent Ottoman attack. Their own incompetence resulted in an Albanian–Greek revolt against them, during which they invited in Ottoman troops to help them put down the revolt. At this time, a number of influential Moreote Greeks and Albanians made private peace with Mehmed. After more years of incompetent rule by the despots, their failure to pay their annual tribute to the Sultan, and finally their own revolt against Ottoman rule, Mehmed came into the Morea in May 1460. Demetrios ended up a prisoner of the Ottomans and his younger brother Thomas fled. By the end of the summer the Ottomans had achieved the submission of virtually all cities possessed by the Greeks.