Serhiy Troyan – Doctor Habilit. of Historical Sciences, Professor, Professor of the University of Rzeszów (Poland). Research interests: world history, international relations, history of diplomacy, research methodology, foreign and domestic policy of Central and Eastern Europe (including modern Ukrainian-Polish relations). Author of more than 500 scientific works in Ukrainian, English, Polish, and Russian, which are devoted to various aspects of the history of international relations. Head of the multi-volume project «The Great War 1914–1918: retrospective analysis».