Edme Jules said Jules Costé was a lawyer and a French composer of operettas and comic opera. Son of Francois Nicolas Augustin Coste (1790-) and Francoise Favyer Hortense (1796-1864), Jules Costé follows in the footsteps of his father and became a lawyer, employed at the Ministry of Finance. He was an amateur music composer. He wrote first with another amateur, Rainulphe Eustache, Count of Osmond, a comic opera in one act: Jacqueline (1855), and a one-act operetta: A full water (1855). He was a member of the Cercle de l'Union or artistic Circle Mirlitons in the Place Vendome, created in 1860 by the Earl of Osmond to promote performances of great music in places other than theaters