The subject of this research is the system of international relations in the late 19th - early 20th centuries. The article defines the main prerequisites for the existing contradictions in the international arena by the beginning of the First World War. The author examined the main interests of political groups that had developed by the beginning of the 20th century. The interpretation of the actions of political actors from the point of view of the implementation of their strategic pans is made. The article examines the key positions of public opinion that reigned in the warring blocs. An attempt was made to create schemes of interaction between the leading world powers by the end of the 19th century and by the beginning of the 20th century. The analysis of the existing military-political blocs by the beginning of the First World War is carried out. The study showed that the contradictions in the system of international relations before the First World War are a process of a long splintering of relations within Europe under the influence of colonial issues and national interests.