The administrative system of Aryans was headed by the king who played the pivotal role. The tribal kingdom (rashtra) consisted of tribes (jana), tribal units (vish) and villages (grama). The nucleus was the family known as kula which was governed by the eldest male member as its head or kulapa. The king was assisted by the elder members of the tribe and by the village headmen.
The purohita or chief priest acted as the priest, astrologer, and adviser had an important role to play. Even the senani or military commander was responsible for the administration system. These two people remained much closer to the king. Spies and messengers were also employed by the king who was endowed with the duty to secretly obtain information about its enemies for the king. The administrative system also had other members like the charioteer, the treasurer, the steward, and the superintendent of dicing who acted under the king.
The Aryans were divided into three social classes when they first came to India. The three major divisions were the warriors or aristocracy, the priests, and the common people. There was no consciousness of caste. Professions were not hereditary hence children had their free choice of occupations. There were also no rules that limited marriages within certain classes or taboos with whom one could eat. The three divisions simply facilitated social and economic organization. The first move in the direction of caste discrimination was taken when the Aryans treated the Dasas as beyond the social pale. It was probably done because of the fear of the Dasas and the fear that by assimilating with them would lead to a loss of Aryan identity. Apparently the distinction was largely based on that of colour as the Dasas were darker and of an alien culture. The Sanskrit word for caste is varna which literally means colour. The colour element of caste was stressed upon throughout this period. This system eventually became deep-rooted in north-Indian Aryan culture. Initially the division was between the Aryans and the non-Aryans. The Aryans were the dvija or twice-born castes, the first being physical birth and the second their initiation into caste status. The caste system consisted of the Kshatriya (warriors and aristocracy), the Brahmin (priests), and the Vaishya (cultivators); the fourth caste, the Sudras who were the Dasas and those of mixed Aryan-Dasa origin.