The twin provinces of Agra and Oudh form a tract, which from the dawn of Hindu civilization has been the home of Hinduism. Its social system is the Hindu social system of northern India. Hindu groups are divided into various castes. This caste system has grown slowly. Discussed in the book is the nature of the caste system in India, its evolution into various subcastes, sectarian castes, new castes, etc. Also described are the various primitive customs which were once prevalent among the various castes. Their significance is purely ethnographical. The appendices contain a list of caste names.