Marie-Juliette Olga ("Lili") Boulanger (French: [bu.lɑ̃.ʒe]; 21 August 1893 – 15 March 1918) was a French composer, the younger sister of the noted composer and composition teacher Nadia Boulanger, and the first female winner of the Prix de Rome composition prize.
A Parisian-born child prodigy, Boulanger's talent was apparent at the age of two, when Gabriel Fauré, a friend of the family and later one of Boulanger's teachers, discovered she had perfect pitch. Her parents, both of whom were musicians, encouraged their daughter's musical education. Her father was 77 years old when Lili was born and she became very attached to him. Her mother, Raissa Myshetskaya (Mischetzky), was a Russian princess who married her Paris Conservatoire teacher, Ernest Boulanger. Her grandfather Frédéric Boulanger had been a noted cellist and her grandmother Juliette a singer. Boulanger accompanied her ten-year-old sister Nadia to classes at the Paris Conservatoire before she was five, shortly thereafter sitting in on classes on music theory and studying organ with Louis Vierne. She also sang and played piano, violin, cello and harp. Her teachers included Marcel Tournier and Alphonse Hasselmans.
In 1912 Boulanger competed in the Prix de Rome but during her performance she collapsed from illness. She returned in 1913 at the age of 19 to win the composition prize for her Faust et Hélène, becoming the first woman composer to win the prize. Nadia had given up entering after four unsuccessful attempts and had focused her efforts upon her sister Lili, first a student of Nadia and then of Paul Vidal, Georges Caussade and Gabriel Fauré—the last of whom was greatly impressed by the young woman's talents and frequently brought songs for her to read. Lili was greatly affected by the 1900 death of her father; many of her works touch on themes of grief and loss. Her work was noted for its colorful harmony and instrumentation and skillful text setting. Aspects of Fauré and Claude Debussy can be seen in her compositions, and Arthur Honegger was influenced by her innovative work.