The article studies the process of peace settlement of the war in Eastern Galicia between 1918 and 1919. The author conducts a comparative analysis of the policy of Poland and the West Ukrainian People’s Republic meant to legitimate power in the disputed region. He also studies the mediation initiative of the Entente and the conflict settlement process during the peace conference in Paris, revealing the motives of the parties’ actions. With reference to a particular example, the article mainly aims to prove that the idea of law and justice was degrading and failing due to the hegemony of western states that assumed the role of world arbiters following the defeat of the German-Austrian alliance. This status let them ignore the principles of international relations and take decisions relying on geopolitical motives and their own imperialist interests. The analysis is made with reference to archival and published sources, i.e. texts of international treaties, minutes of the Supreme War Council’s meetings, diplomatic correspondence, reports of povit commissars of the West Ukrainian People’s Republic, appeals on behalf of the Polish population of Galicia, etc. Additionally, the author takes into account the achievements of modern historiography relating to the issue in question in the Russian, Polish, Ukrainian, and English languages.