Cœurdoux first studied Telugu, a major language of the Dravidian group, in order to work in the region of present Andhra Pradesh, in particular Krishnapuram, Bukkapuram, and Darmavaram Madigubba (1736 to 1737).
As superior, he was obliged, against his own inclinations, to enforce the very restrictive decree of Pope Benedict XIV (12 September 1744 ) on the "Malabar rites".
A disciple of the Jesuit philologist Jean Calmette, whom he knew personally in India, he was particularly interested in comparative linguistics.
In a Mémoire sent to the Académie des inscriptions et belles-lettres (France) in 1767, he demonstrated the similarity between the Sanskrit, Latin, Greek, and even German and Russian.
[1] It was only in the late 20th century, thanks to the work of J.J. Godfrey and Sylvia Murr (see Bibliography), that Cœurdoux's role in the discovery of the relationship between Sanskrit and the ancient languages of Europe had been re-established.