Darius Milhaud (French: [daʁjys mijo], Provençal: [miˈjawt]; 4 September 1892 – 22 June 1974) was a French composer, conductor, and teacher. He was a member of Les Six—also known as The Group of Six—and one of the most prolific composers of the 20th century. His compositions are influenced by jazz and Brazilian music and make extensive use of polytonality. Milhaud is considered one of the key modernist composers. He taught many future jazz and classical composers, including Burt Bacharach, Dave Brubeck, Philip Glass, Steve Reich, György Kurtág, Karlheinz Stockhausen and Iannis Xenakis among others.

Milhaud was born in Marseille, the son of Sophie (Allatini) and Gad Gabriel Milhaud. He grew up in Aix-en-Provence, which he regarded as his true ancestral city. His was a long-established Jewish family of the Comtat Venaissin—a secluded region of Provence—with roots traceable there at least to the 15th century. On his father's side, Milhaud's Jewish lineage was thus neither Ashkenazi nor Sephardi, but specifically Provençal—dating to Jewish settlement in that part of France as early as the first centuries of the Common Era. Milhaud's mother was partly Sephardi on her father's side, via a Sephardi family from Italy.

Milhaud began as a violinist, later turning to composition. He studied at the Paris Conservatory, where he met fellow Les Six members Arthur Honegger and Germaine Tailleferre. He studied composition with Charles-Marie Widor and harmony and counterpoint with André Gedalge. He also studied privately with Vincent d'Indy. From 1917 to 1919, he served as secretary to Paul Claudel, the poet and dramatist who was then the French ambassador to Brazil, and with whom Milhaud collaborated for many years, writing music for many of his poems and plays. In Brazil, they collaborated on the ballet L'Homme et son désir.

On his return to France, Milhaud composed works influenced by Brazilian popular music, including songs by pianist and composer Ernesto Nazareth. Le Bœuf sur le toit includes melodies by Nazareth and other popular Brazilian composers, and evokes the sounds of Carnaval. Among the melodies is a Carnaval tune by the name of "The Bull on the Roof" (in Portuguese, which he translated to French 'Le boeuf sur le toit', known in English as 'The Ox on the Roof'). He also produced Saudades do Brasil, a suite of 12 dances evoking 12 Rio de Janeiro neighborhoods. Shortly after the original piano version appeared, he orchestrated the suite.

Contemporary European influences were also important. Milhaud dedicated his Fifth String Quartet (1920) to Arnold Schoenberg, and the next year conducted both the French and British premieres of Pierrot lunaire after multiple rehearsals. On a trip to the United States in 1922, Milhaud heard "authentic" jazz for the first time, on the streets of Harlem, which greatly influenced his music. The next year, he completed La création du monde (The Creation of the World), using ideas and idioms from jazz, cast as a ballet in six continuous dance scenes.

In 1925, Milhaud married his cousin Madeleine, an actress and reciter. In 1930 she gave birth to a son, the painter and sculptor Daniel Milhaud, who was the couple's only child.

Nazi Germany's invasion of France forced the Milhauds to leave France in 1940. They immigrated to the U.S. (Milhaud's Jewish background made it impossible for him to return to France until it was liberated). He secured a teaching post at Mills College in Oakland, California, where he composed the opera Bolivar (1943) and collaborated with Henri Temianka and the Paganini Quartet. In an extraordinary concert there in 1949, the Budapest Quartet performed his 14th String Quartet, followed by the Paganini Quartet's performance of his 15th; and then both ensembles played the two pieces together as an octet. In 1950, these pieces were performed at the Aspen Music Festival by the Paganini and Juilliard String Quartets.

On June 13,1945, his Suite Francaise, – Normandie, Bretagne, Ile de France, Alsace-Lorraine, Provence, had its World Premiere performance at the Naumburg Orchestral Concerts, in the Naumburg Bandshell, Central Park, in the summer series.