This document summarizes the evolution of international society from ancient times to the modern era. It discusses key concepts like sovereign equality and non-intervention that form the basis of modern international society established by the Peace of Westphalia in 1648. The document then outlines how international society has globalized over time through decolonization, the end of the Cold War, and increasing challenges from globalization. It concludes by briefly introducing a case study on the Iranian Revolution of 1979.