When Manuel returned to Constantinople in 1403, he refused to carry out his promised gift of Salonika. Before the battle of Angora had decided the fate of Bayezid, and the issue between the Turks and the Mongols was still uncertain, John Palaiologos had agreed—it was said—to surrender Constantinople and become a tributary of the Sultan, in the event of a Turkish victory. This was Manuel’s, excuse for refusing to allow his nephew to reside at Salonika and for banishing him to Lemnos. John thereupon appealed to his father-in-law for assistance, and Francesco, early in 1403, sailed with five vessels to attack Salonika. Hearing that Boucicault, then French governor of Genoa, whose interest in Lesbos had just been evinced by the despatch of an embassy thither, was once more in the Levant on a punitive expedition against King Janus of Cyprus, who had besieged the Genoese colony of Famagosta, Francesco despatched a vessel to meet the Marshal, reminding him that he had been a witness of the Emperor’s promise and begging him to aid in taking Salonika[553]. Boucicault did not accede to this request; on the contrary, two vessels from Lesbos and two from Ænos went to assist him in his operations against the King of Cyprus, and remained with him till shortly before he reached the Venetian colony of Modon on his homeward voyage. Manuel ended by bestowing Salonika upon John Palaiologos, but the attacks made by Boucicault upon Venetian trade in the Levant and the consequent hostilities cost Nicolò Gattilusio, owing to his Genoese origin, the loss of 3000 ducats in gold, seized by the Venetians at Modon[554].