The pattern of Muslim population in India reflects the contribution of a number of factors: proselytization, migration, and natural growth rate. The partition of the country in 1947 made its own important contribution, effecting profound changes in the distribution pattern of Muslims that resulted in the migration of about 10 million people to and from the newly created country of Pakistan, but natural growth has been the chief determinant of the growth of India’s Muslim population during the post-independence period. Relatively high growth of the Muslim population in this period is mainly attributable to two factors: a higher incidence of poverty, which is closely correlated with higher fertility; and the persistence of a pro-natal attitude among this population. Higher concentrations of Muslims are found in two types of areas: (a) those that experienced a longer duration of Muslim rule and (b) those located at the margins of the Hindu heartland.