[1] He was the son of the diplomat Pierre de Margerie (1861-1942), who was Secretary General of the Ministry of Foreign Affairs in 1914 and French Ambassador to Berlin after World War I.

De Margerie studied at the École Libre des Sciences Politiques, and began his diplomatic career as the Secretary of the French Embassy in London before World War II, in the office of Paul Reynaud.

[1] He attended the Briare conference on 11 June 1940 between the French and British leaders, and wrote the official account.

[2] After World War II, de Margerie played an important role in the reconciliation with Germany.

He was ambassador to Bonn in 1963, with the signing of the Élysée Treaty between Charles de Gaulle and Konrad Adenauer.