She is known for her research into the social history of ancient India, especially the evolution of the caste system and the development and absorption of regional deities into the Hindu pantheon.

[3] Jaiswal showed that neither skin colour and notions of race were the basis of caste (varna) differentiation.

Rather, it was the unequal access to economic and political power that entrenched status distinctions and crystallised the hierarchy.

[4] She also determined that there were consequences to specialist economic roles, endogamy and hierarchical society: the systematic suppression of women as a class.

[3] In particular, she pointed out that there was insufficient surplus production of goods in the Rig Vedic period to allow any section of society to withdraw from economic activity.