In 1791, the celebrated Scottish historian, William Robertson, published his final work, An Historical Disquisition concerning the Knowledge which the Ancients had of India, in which he explored the commercial and cultural connections of India and the West from ancient times to the end of the fifteenth century. This article considers Robertson's Historical Disquisition within the contexts of the Scottish Enlightenment, the early British ‘orientalist’ movement, and the expansion of British dominion in India. It argues that while the work reflected the assumptions and approaches of the British orientalist school, Robertson – sensitive to criticisms that his previous History of America had been too dismissive of Amerindian cultures – went further than many orientalists in his positive portrayal of Indian culture and his opposition to an interventionist imperial policy. Indeed, the work was largely directed to preserving the ancient and sophisticated Indian civilisation from Western cultural imperialism. The article further suggests that Robertson's favourable view of what he perceived as monotheist beliefs underlying ‘classical’ Hinduism reveals much about his own religious attitudes as a clergyman and leader of the ‘moderate’ party in the Church of Scotland. His history of India would be under-valued in Britain (despite its large sales), in large part because his apology for Hinduism and his critique of Christian missions ran counter to the rising tide of the evangelical revival. However, it had a considerable role in promoting interest in India on the European continent, and it represented one of the more significant achievements of the late Scottish Enlightenment.