Edgar Dreyfus was a banker following in the tradition of the Dreyfus family, which had a history of involvement in the banking and shipping industries.

The Dreyfus house in Paris was one of the first to be occupied by the Gestapo when the Germans occupied the city in 1940. The family, comprising father and mother, Edgar and Yvonne, and their two daughters, Viviane and Christiane, fled to the south of France, staying in Perpignan, Marseille and Cannes. When the Italians capitulated in 1943 they went into hiding in Pau and later walked to Spain. They were accompanied by a cousin, Manon Levenvach, who had managed to escape deportation by jumping from a train. She stayed with the Dreyfus family in Spain for the remainder of the war.