Independence in international relations refers to the political, economic, and military autonomy of a state from external influence or control. This can encompass a variety of aspects, such as the ability of a state to make its own foreign policy decisions, control its own natural resources, and maintain its own military. Independence is widely considered to be a key component of state sovereignty and a necessary condition for a state to effectively participate in the international system.
Source: Nye, J. S. (1971). Peace in parts: Integration and conflict in regional organization. Boston: Little, Brown.