Not since l931 has any Census taken up the issue of caste. The excuse for having a “caste enumeration” in 2011 did not meet this criterion. As a result, the only really solid information we have about the caste map of India comes from 80 years ago. The data is old, but there is reason to think that no really qualitative changes have taken place.
The caste map shows the distribution of the various castes. The largest percentage of Dalits is in northern India, in the Chamar-dominated belt of UP, Haryana and Bihar. Here the percentage is nearly 20%. OBCs are prevalent everywhere, with solid majorities in Maharashtra (the Maratha-Kunbi group) and groups such as Kapus, Vokkaligas and Kammas in the neighboring states of Andhra and Karnataka, Kunbis in parts of Gujarat. Jats and Kurmis in north India are an equivalent group, as are Yadavs. Rajputs were numerous in some regions, as were Vaishyas in a small part of Gujarat.
This caste map was put together by Joseph Schwartzberg, then at the University of Chicago. Would that up-to-date Census data were available for similar maps.