Caste was central to the social life of these north Indian kingdoms. Early Aryan society had distinguished among the warrior elite, the priests, ordinary tribesmen, and conquered subjects. These distinctions gradually evolved into the caste system, which divided society into strictly defined hereditary groups. Society was conceived of as four hierarchical strata whose members did not eat with or marry each other. These strata, or varnas, were Brahmin (priests), Kshatriya (warriors and officials), Vaishya (merchants), and Shudra (peasants and laborers). The caste system thus allowed the numerically outnumbered Aryans to maintain dominance over their subjects and not be culturally absorbed by them.

Social and religious attitudes supported the caste system. Aryans considered the work of artisans impure. They left all such work to the local people, who were probably superior to them in these arts anyway. Trade, by contrast, was not viewed as demeaning. Brahmanic texts of the period refer to trade as equal in value to farming, serving the king, or being a priest.

As priests, the Brahmins were expected to memorize every syllable and tone of the Vedas so that their rituals would please the gods. They not only conducted the traditional ceremonies but also developed new ones for new circumstances. As agriculture became more important to the Aryans, for example, Brahmins acted as agents of Agni, the god of fire, to purify the land for crops. The Brahmins also knew the formulas and spells that were effective against diseases and calamities.

Those without places in the four varnas — that is, newly conquered peoples and those who had lost their caste status through violations of ritual — were outcastes. That simply meant that they belonged to no caste. In time, some of them became “untouchables” because they were “impure.” They were scorned because they earned their living by performing such “polluting” jobs as slaughtering animals and dressing skins.

Slavery was a feature of early social life in India. People captured in battle often became slaves, but captives could also be ransomed by their families. Later, slavery was less connected with warfare and became more of an economic and social institution. At birth, slave children automatically became the slaves of their parents’ masters. Indian slaves could be bought, used as collateral, or given away.

Like most nomadic tribes, the Aryans were patrilineal and patriarchal (tracing descent through males and placing power in the senior men of the family). Thus the roles of women in Aryan society probably were more subordinate than were the roles of women in local Dravidian groups, many of which were matrilineal (tracing descent through females). But even in Aryan society women were treated somewhat more favorably than in later Indian society. In epics such as the Ramayana, women are often portrayed as forceful personalities, able to achieve their goals both by using feminine ploys to cajole men and by direct action.