Context and Background

The Cambridge Companion to Modern Indian Culture. Cambridge; New York: Cambridge UP, 2012. Cambridge Companions to Culture.

Caste, Society and Politics in India from the Eighteenth Century to the Modern Age. Cambridge, [England]: New York: Cambridge UP, 1999. New Cambridge History of India; IV, 3.

The Economy of Modern India, 1860-1970. Cambridge [England]; New York: Cambridge UP, 1993. New Cambridge History of India ; III, 3.

Women in Modern India. Cambridge [England]; New York: Cambridge UP, 1996. New Cambridge History of India ; IV, 2.

Banglapedia - the National Encyclopedia of Bangladesh is a comprehensive reference work on Bangladesh from high ancient period to date.

Historical dictionary of India, by Surjit Mansingh. 2nd ed. Lanham, Md. : Scarecrow Press, 2006, 833 p.
FindIt@Harvard

India today: an encyclopedia of life in the Republic, ed. by Arnold P. Kaminsky and Roger D. Long. Santa Barbara, Calif.: ABC-CLIO, 2011. 2 v.
FindIt@Harvard

Brill's Encyclopedia of Hinduism

Oxford Encyclopedia of the Islamic World: Digital Collection
Offers extensive comparative and systematic analyses of Islamic beliefs, institutions, movements, practices, and peoples on an international scale. Articles range from brief essays to major interpretive and synthetic treatments of topics such as the Islamic state, pilgrimage, law, marriage, and foreign relations.

The Oxford History of Islam
Introductory but detailed articles on Islam from its origins to present day, in various geographic regions. 

Encyclopaedia of Islam Online offers over 13,000 articles on topics in Middle Eastern and Islamic studies.

Encyclopaedia of Islam, 3rd ed., offers enhanced coverage of 20th century Islam.