Estimates of Indian GDP are constructed from the output side for 1600-1871, and combined with population data. Indian per capita GDP declined steadily during the seventeenth and eighteenth centuries before stabilising during the nineteenth century. As British growth increased from the mid-seventeenth century, India fell increasingly behind. Whereas in 1600, Indian per capita GDP was over 60 per cent of the British level, by 1871 it had fallen to less than 15 per cent. These estimates place the origins of the Great Divergence firmly in the early modern period, but also suggest a relatively prosperous India at the height of the Mughal Empire. They also suggest a period of "strong" deindustrialisation during the first three decades of the nineteenth century, with a small decline of industrial output rather than just a declining share of industry in economic activity.JEL classification: N10, N30, N35, O10, O57