The organisation of a society capable of managing the complexity of a large number of people and meeting their manifold needs and life-requirements, brings about certain forms which have tended to replicate themselves in diverse societies, both Western and Eastern. Any form of societal organisation involves a certain amount of required uniformity and certainty to ensure all the needs are being met. Such foundations have been developed using relatively fixed systems of social hierarchy, so that the society could count on certain functions being carried out by certain people, and there was a process for continuity of those functions into the future. At the same time, individuals were certain about their place and role in the society. It is not our purpose here to examine the specific forms or their inherent strengths or weaknesses; rather, we are looking at the historical basis of the development of such hierarchies and the interplay with the development of the nation-unit of societal development.
Sri Aurobindo notes: “But it is noticeable that both in Europe and Asia there was a common tendency, which we cannot trace to any close interchange of ideas and must therefore attribute to the operation of the same natural cause and necessity, towards the evolution of a social hierarchy based on a division according to four different social activities,– spiritual function, political domination and the double economic function of mercantile production and interchange and dependent labour or service. The spirit, form and equipoise worked out were very different in different parts of the world according to the bent of the community and its circumstances, but the initial principle was almost identical. The motive-force everywhere was the necessity of a large effective form of common social life marked by fixity of status through which individual and small communal interests might be brought under the yoke of a sufficient religious, political and economic unity and likeness.”
While different models evolved, particularly in the Islamic world, it must be noted that they did not tend to lead to strong independent nation-units as in those places which created such a social hierarchy.
Sri Aurobindo, The Ideal of Human Unity, Part One, Chapter 13, The Formation of the Nation-Unit — The Three Stages, pp. 104-105