In July 1939, Winnaretta received notification that she was to be promoted to the rank of Officer of the Legion of Honor for “fifty-four years of service rendered to the sciences, letters, and the arts.” The nominating committee cited her numerous acts of generosity for the public good, including her beneficence towards to the Salvation Army and the Hôpital Saint-Louis, and her countless activities on behalf of the arts: her organization of concerts in France and abroad, her articles in the Renaissance latine and the Revue de Paris, and the exhibitions of her art at the official Salon and the Galerie Charpentier. Her creation of the Fondation Singer-Polignac was cited as the culminating gesture of her long career as a grande mécène.

The subject of honor—of a more personal sort—was discussed when Winnaretta's nephew Edmond de Polignac came to visit at avenue Henri- Martin. As the expectation of war loomed, the imminent conscription of young men was on the minds of French families everywhere. Anticipating his “call to the flag,” Eddy had come to bid farewell to his aunt. In parting, Winnaretta said to her godson, “Never forget that, no matter what happens, you are the son of your father—a man of honor par excellence—and that you are the nephew of the uncle for whom you were named, the only man besides my own father that I respected and that I loved. Remember that you are bound, by your blood and by your name, to honor your family.”

Within a month Edmond de Polignac would be conscripted and sent to defend his country on foreign soil. At almost the same time, on 10 August 1939, Winnaretta's brother Franklin Singer, the youngest of Isaac's twenty-four children, died in Paris. Winnaretta accompanied the body back to England for its burial in the Singer family crypt. As the boat bearing the coffin approached Torquay, Winnaretta thought of the lines by Tennyson: