Geopolitics (Political geography is part of human geography) is the study of the effects of Earth's geography on politics and international physical relations. While geopolitics usually refers to countries and relations between them, it may also focus on two other kinds of states: de facto independent states with limited international recognition and relations between sub-national geopolitical entities, such as the federated states that make up a federation, confederation or a quasi-federal system.

geopolitics is a method of studying foreign policy to understand, explain, and predict international political behavior through geographical variables. These include area studies, climate, topography, demography, natural resources, and applied science of the region being evaluated.

Geopolitics focuses on political power linked to a geographic space. In particular, territorial waters and land territory in correlation with diplomatic history. Topics of geopolitics include relations between the interests of international political actors focused within an area, a space, or a geographical element, relations which create a geopolitical system. Critical geopolitics deconstructs classical geopolitical theories, by showing their political/ideological functions for great powers. There are some works that discuss the geopolitics of renewable energy.