International Politics has had a tremendous transformation since the end of the Cold War, even though the nature of the system remains the same, that is, the Anarchy made up of Sovereign States, however, changes and developments that are different from those in the past have taken place within the system itself. Globalization, for instance, is a phenomenon that has expanded from the realm of economy to those of politics, culture, and others, covering a broad range of contents, and poses a challenge towards states’ established sovereignty, power, and political status. Others, such as the rapid growth of international organizations (governmental and non-governmental), as well as the gradual attention paid to environmental and human rights issues, are also making an impact to the internals of the post-Cold War international system. These impacts present an evident limit in the capacity of sovereign states, and an increased necessity of the post-Cold War international society for legal norms. These phenomena are transforming the international political system that traditional realism viewed as state-centric into a neo-Medieval one that resembles Medievalism. In such new system, state actors will lose their absolute supremacy and dominant status, while the development of international legal norms will simultaneously adapt to the changes accordingly. This article attempts to understand the transformations within the post-Cold War international political system, and also their probable effects on international legal norms.