With the establishment of the League of Nations, The scope of the study of international relations further widened and now the study of international institution or organizations was also included in it. After Second World War the frontier of the study of international relations further widened. Firstly, it was realized that as foreign policy and military policy are closely related, study of war and its strategy should also find place in the study of international relations. Secondly, with the advancement in the field of psychology, certain people thought it proper to study international relations through personality and background analysis. These people started a study of the behavior of leaders, groups, and the role of public opinion. Thirdly, the world war gave a break to the study of certain areas or region. In the post-war period the study of areas or regions assumed great importance.

Thus we see that the scope of the study of international relations want on increasing day by day. Now international relations include “The study of diplomatic history, international politics, internationl organization and administration, international law, area studies as well as a study of the motivation of inter-state relations”.