The son of Ludovic Halévy, Daniel was born in and died in Paris.

Social historians have acknowledged Halévy for his "Essai sur l'accélération de l'histoire" (Essay on the Acceleration of History), while he remains largely overlooked by literary scholars.

With André Spire, whom he had met in the Cooperation des Idées, he founded the Université populaire.

Although he personally abhorred Italian Fascism and German National Socialism, he went on to support Marshal Philippe Pétain's Vichy regime.

[2] The radicalisation of the right wing would accelerate after the election of the Popular Front in 1936 and the Spanish Civil War (1936–39).