The Failed Ottoman Campaign of Constantinople in 1438

This article considers the history of the campaign of Ottoman Sultan Murad II to Constantinople that failed in 1438. The study is based on the reports of Byzantine historians Georgios Sphrantzes and Sylvestre Syropulos and Castilian traveller Pero Tafur. Based on an analysis of the sources, the author describes the Byzantine-Ottoman relations in the 1430s and defines the role of the Turkish factor in the context of negotiations between Byzantium and the West about the unification of churches. The study de­monstrates that the Ottomans planned an attack on Constantinople in 1438 in order to thwart the Uniate negotiations. The departure of Emperor John VIII Palaiologos to the Council of Ferrara-Florence in November 1437 displeased the sultan, who feared a political rapprochement of the Greeks with Western countries. According to sources, the campaign did not take place, because grand vizier Halil-Pasha convinced the Sultan to abandon this plan. The author of the article suggests that Murad II was stopped from aggression by the agreement with Byzantium, under which the Empire recognised itself as a vassal of the Ottoman sultan, the previous experience of military confrontation with the Greeks, as well as the difficult foreign policy situation in the Balkans. However, the threat of an Ottoman attack on the Byzantine capital influenced the negotiations of the Greek delegation with the papacy. The issue of sending ships to the aid of Constantinople by the papacy and Venice was being actively discussed throughout the year. Even when the issue of providing emergency assistance to the city lost its urgency, he did not leave the political agenda of negotiations at the Council. The Greeks continued to play the “Turkish card” in an effort to make the papacy move from promises to decisive action and demonstrate the political will to provide real military assistance to the Byzantine Empire.