A study of world history shows that States have arisen at different times in different countries. They assumed different forms and organizations in different countries of the people, and of government and law at different ties and places. Hence the actual structures and forms of the States have always varied. Even, the evolution of the State in a country did not remain the same.* Having once started on the course of political evolution, some people continued with it while with other it came to a standstill, or even regressed to earlier forms. While one State has gone a step back, another has gone two steps forward. That is why we do not find any uniformity and continuity in the evolution of the States in different countries and peoples.
A brief description of the stages through which the States have actually evolved from primitive times to the present day would be useful and instructive for a student of Political Science. It will provide him a frame of reference for the study and understanding of the States and political theories and to foresee the future evolution of the State. Broadly speaking, the State has evolved through the following forms or stages:
1. Stateless Societies of the primitive times.
2. The Tribal Kingdoms.
3. The Oriental Empires.
4. The Greek City-States.
5. The Roman Empire.
6. The Feudal States.
7. The National States of the modem times.