From the sixth century onwards, some changes occurred in social organization.
In the Gangetic plains in north India, the vaishyas were regarded as free peasants, but land grants created landlords between the peasants, on the one hand, and the king, on the other, so the vaishyas were reduced to the level of the shudras.
This modified the old brahmanical order, which spread from north India into Bengal and south India as a result of land grants to the brahmanas, brought from the north from the fifth—sixth centuries onwards. In the outlying areas there were largely two orders, brahmanas and shudras.
Frequent seizures of power and land grants gave rise to several categories of landed people. When a person acquired land and power, he naturally sought a high position in society. He might belong to a lower Varna, but he was favoured with generous land grants by his master. This created difficulties because, though economically well off, socially and ritually he was low. According to the Dharmashastras, social positions had hitherto been largely regulated by the Varna system. The people were divided into four varnas, the brahmanas being the highest and the shudras the lowest.
The economic rights of a person were also determined by the Varna to which he belonged. So some changes had to be made in the written texts to recognize the position of the new landed classes. An astrologer of the sixth century, Varahamihira, prescribed houses in sizes that varied according to the varna, as was the ancient practice, but he also fixed the size according to the grades of various classes of ruling chiefs. Thus, formerly all things in society were graded according to the varnas, but now they were also determined by a person’s possession of land.
Though some law-books allowed niyoga (levirate) or widow remarriage, these concessions were confined to the women of the lower orders. From the very outset, women were denied property rights, and immovable property could not be inherited by them. From the seventh century onwards, numerous castes were created.
A Purana of the eighth century states that thousands of mixed castes were produced by the connection of vaishya women with men of lower castes. This implies that the shudras and untouchables were divided into countless sub-castes, as were the brahmanas and Rajputs who constituted an important element in Indian polity and society around the seventh century.
The number of castes increased given the nature of the economy in which people could not move from one place to another. Although people living in different areas followed the same occupation, they became divided into sub-castes in relation to the territory to which they belonged.
In addition, many tribal people were admitted into brahmanical society on the basis of land grants given to the brahmanas in the aboriginal tracts. Most of these people were enrolled as shudras and mixed castes. Every tribe or kin group was now given the status of a separate caste in brahmanical society.