Тhe history of Knights Hospitaller in Rhodes (in the period between 1300 – 1421 AD) has been treated in the modern historiography in several different aspects and contexts up to now. Reasonably it has been represented as a part of the history of the crusade movement and therefore has been a subject of increased interest by the scholars of the Late Crusades. For the medievalists the development of the Order of St. John in that period has been not less interesting as an organic part of the history of the Latin States in the Levant. But even now the world’s medieval studies lack a separate scientific monography dealing with the stay of the order in Rhodes, connected to its meaning in the context of the history of the Balkan medieval states. According to me it is necessary to be presented this point of view of the history of the Knights of Rhodes. The very position of the centre of the possessions of the Knights Hospitaller, their headquarters – the isle of Rhodes, that actually justified their existence, involved them into participation in Balkan politics through the XIV – XVth Centuries. During that fateful period the Balkans have increasingly been turning into a borderland between the civilizations – a zone of extremely intensified contacts between the East and the West, the Islam and the Christianity. As a matter of fact the leading factors that had influence over the peninsula in this age are the relations with the Muslim East and in particular with Asia Minor, from where came the conquerors and for long the future masters of the Balkans – namely the Ottoman Turks. The problem of complicated political relations in the Balkans during that period, and the role that the Order of St. John played in it is my main subject of interest and aim in mine PhD-thesis with which I hope to bear upon its clarification.