He was the founder of the Ballet de l'Opéra at Monte Carlo and was the younger brother of the Socialist Prime Minister of France, Léon Blum.

At the turn of the 20th century he was an editor at the Parisian literary journal Gil Blas and a popular theatre critic.

He saved threatened artwork from Amiens Cathedral and earned the French Croix de Guerre.

[2][3] He became director of plays and operettas at Monte Carlo in 1924,[3] where Sergei Diaghilev's Ballets Russes was based.

[2] In 1931, Blum was hired by Louis II, Prince of Monaco, to create a ballet company that would continue the work and legacy of the late Diaghilev (who had died in 1929).