This research suggests an interpretation of the reasons behind the Byzantine attack on the Turkish fort of Gallipoli in spring 1410. The citadel that controlled Dardanelles was attacked by a squadron of eight ships. This operation is considered not successful. However, there are reasons to consider that initially Greeks did not plan to take the town. The search for the proofs should be in the sphere of international relations. In the period in question, the Byzantine policy was influenced by contradictions between Venice and Hungarian king Sigismund of Luxembourg concerning Dalmatia. Their interests were also connected with Gallipoli, so the question of the status of the fort could only aggravate their relations. The incipient conflict was dangerous for Byzantium. The Turkish factor was also important in this conflict: one more time, it turned against Byzantium and did not allow it to maintain the peace with the Ottomans concluded in 1403. The Byzantine emperor’s reaction to the crisis can be considered as an attempt of meditation by renewal of the treaty with the Turks, with participation of Western states. The main problem was king Sigismund’s position: a contact with him became necessary. In spring 1410, Byzantine diplomats along with the Pope prepared conditions for the meeting with the Hungarian ambassador in Italy. However, Sigismund’s desirable reaction followed just after the Byzantine attack on Gallipoli. From the analysis of the facts and chronology, there are reasons to conclude that the military operation in question was planned specifically to provoke the king to negotiations, which took place in Bologna in June of the same year. ; В исследовании предлагается версия, объясняющая причины нападения византийцев на турецкую крепость Галлиполи весной 1410 г. Цитадель, которая контролировала Дарданеллы, была тогда атакована эскадрой из восьми кораблей. Считается, что операция была безуспешной. Однако есть основания предполагать, что греки изначально не намеревались захватывать город. Доказательства ...