His doctoral thesis, submitted in 1925, was La valeur du parfait dans les hymnes védiques.
After a short time at the Faculté de lettres in Lyon, he moved to L'École des hautes études and then to the Sorbonne where he succeeded Alfred A. Foucher.
He left to one side archaeology, political history and Buddhism and concentrated firmly on the tradition that, beginning with the Rig Veda, runs through all aspects of belief and practice right up to the present.
For forty years he regularly published articles and books that were often voluminous, were based on original research, and are of considerable merit.
"[2] Louis Renou was director of the Institut de civilisation indienne and attended regularly meetings of the Académie and the Societé Asiatique.