Scelle attended the law faculty and the École Libre des Sciences Politiques in Paris, where he was awarded a prize for his thesis, "La traite négrière aux Indes de Castille", written under the supervision of Antoine Pillet.
[1] He published the first volume of the Précis de droit des gens shortly before joining the University of Paris (1933) where he taught Public International Law until his retirement in 1948.
He exerted a considerable influence on the generation which dominated both French public service and academic law circles from the 1930s until today.
Scelle supported the codification of the laws of war in an international convention.
In this regard, he believed that even UN forces "did not stand above all law", and was in favor of subjecting them as well to the provisions of the Geneva convention.