Persecuted ethnic and religious minorities, who are victims of discrimination by the state and subjected to recurring communal and racial atrocities have been coming over to India in droves since the Partition of 1947. For a brief period of three-and-a-half years after liberation, Bangladesh was committed to secular governance when the Hindus and other minorities experienced some let up in the persecution by the majority Muslim community. Ever since 1975, the country has gone through a steady process of Islamisation, ranging from deletion of secularism from the constitution to legitimisation of banned communal and fundamentalist Islamist parties to declaration of Islam as the state religion of Bangladesh. The consequent heightening of insecurity among the
minorities intensified migration of the Hindus to the bordering states of India.
The second type of migrants consist of pauperised landless Muslims from rural Bangladesh in search of employment. The in-flow of economic migrants began during the 1974 famine in Bangladesh and has continued unabated ever since.
There has been no census of immigrants yet, but academics, government agencies, research organisations and demographers estimate 15-20 million migrants have found their way to different Indian states in the last three decades, the ratio of Hindu-Muslim immigrants being approximately 1:3.
While the migration pressure is understandably on the border states (Assam, West Bengal, Meghalaya and Tripura), significant numbers have traveled further afield and have been living in concentration in metropolitan cities like Delhi, Mumbai, Ahmedabad, Jaipur and a host of other urban conglomerates.
http://web.mit.edu/cis/www/migration/pubs/rrwp/chandan_nandy_immigrants.pdf
never knew it.
