From 1391 until the advent of Timur, Constantinople was blockaded on the land side.[478] The Galata garrison and the posts at Kutchuk and Buyuk Tchekmedje were always alert to bully and harass travellers and provision sellers. The Grand Vizier, Ali pasha, used the grandson and namesake of John V Palaeologos to make trouble for Manuel. It was in his blood to become the willing tool of the Osmanlis. In 1393, Ali pasha tried to get the inhabitants of the city to depose Manuel in order that John, as heir of the older son of the late emperor, might take the place which was rightfully his.[479] Two years later John actually attacked the city with Ottoman troops, but was repulsed.[480] The overtures of Manuel for aid and money from Christian princes were received with little enthusiasm. On account of the schism in the Latin Church, Manuel could look for no papal support. Venice refused his offer to sell Lemnos.[481] The time had passed when the Senate set even the slightest monetary value upon a Byzantine deed of sale to an Aegaean island. In 1395, at Serres, Bayezid held his first court as heir of the Caesars. He summoned before him Manuel and Theodore and John, the son of Andronicus. Theodore, who had been ruling in the Morea (Peloponnesus), sole remaining Byzantine theme, was charged with having encroached upon the rights of the lord of Monembasia. The few remaining Serbian princes were also present. Bayezid contemplated ridding himself altogether of the Byzantine imperial family. In fact, he ordered the death of all the Palaeologi. Ali pasha succeeded in putting off the execution long enough for Bayezid to change his mind. The sentence was revoked, but warning was given by cutting off the hands and putting out the eyes of several Byzantine dignitaries. The Palaeologi, and Constantinople, had been saved only by the intervention of a creature of Bayezid’s, who did not want to see the imperial family perish and the imperial city fall because these ghosts of princes were a source of revenue to him! The peril at Serres had been so real that the Byzantine and Serbian princes plotted immediately to throw off the Ottoman yoke, and swore to each other that they would never again answer a summons from Bayezid. The compact was sealed by the marriage of Irene, daughter of Constantine Dragash, to Manuel.[482] But Dragash died shortly after the marriage,[483] and Vuk Brankovitch died three years later.[484] They were the last of the Serbians of Dushan’s following in Macedonia. The disaster of Nicopolis soon crushed the hopes of the conspirators. VI