We shall see that when the Aryan settlements shifted east to the Middle and Eastern Gangetic Valley, they entered into a new and more complex form of agricultural production. In this new context of greater social control and increased stratification, a new state form would eventually develop. However, in the meantime, through a thousand years, the dominant social form in north India was that of segmented units, the four varnas which developed smaller units, castes or jatis, within the varna system of categorization. As the traders and military elites of north India extended their contact with other parts of India, the varna system of four categories would not necessarily be adopted; in the south there were only two categories, Brahmin and non-Brahmin. However, the notion of accommodating new groups with the customs into a segmented system of organization would dominated. Caste in different forms would become the dominant social form
of social organization.