Igor Fyodorovich Stravinsky (17 June [O.S. 5 June] 1882 – 6 April 1971) was a Russian composer, conductor, and pianist with citizenship in France (from 1934) and the United States (from 1945). He is widely considered one of the most important and influential composers of the 20th century and a pivotal figure in modernist music for his approach to asymmetrical rhythm.

Stravinsky met Russian composer Nikolai Rimsky-Korsakov in 1902 and studied under him until 1908. Attending the premiere of Stravinsky's Scherzo fantastique and Feu d'artifice in February 1909 was Russian impresario Sergei Diaghilev, who had just formed the Ballets Russes company. In the following years, Diaghilev commissioned Stravinsky to write three ballets: The Firebird (1910), Petrushka (1911), and The Rite of Spring (1913), the last of which brought him international fame after the near-riot at the premiere and changed the way composers understood rhythmic structure.

Stravinsky's compositional career is divided into three periods: his Russian period (1913–1920), his neoclassical period (1920–1951), and his serial period (1954–1968). Stravinsky's Russian period was characterised by influence from other Russian composers like Rimsky-Korsakov, Lyadov, and Tcherepnin, and use of Russian folk songs and themes in works like The Nightingale (1914) and Les noces (1917). His neoclassical period exhibited themes and techniques from the classical period, like the use of the sonata form in his Octet (1923) and use of Greek mythological themes in works like Apollon musagète (1927), Oedipus rex (1927), and Persephone (1935). In his serial period, Stravinsky turned towards compositional techniques from the Second Viennese School like Arnold Schoenberg's twelve-tone technique. In Memoriam Dylan Thomas (1954) was the first of his compositions to be fully based on the technique, and Canticum Sacrum (1956) was his first to be based on a tone row. Additionally, Stravinsky used sacred themes in works like Threni (1958) and The Flood (1962).

Stravinsky explored many kinds of art and collaborated with many different artists throughout his career, including Pablo Picasso, Jean Cocteau, W. H. Auden, George Balanchine, and André Gide. His students included Robert Strassburg in the 1940s and Robert Craft and Warren Zevon in the 1960s. In addition, he often performed in public, touring across the world in the later part of his life. Stravinsky was a devout member of the Russian Orthodox Church for most of his life, believing that his musical talent was a gift from God.

Stravinsky was one of the most important composers of the 20th century. Composer Philip Glass wrote in 1998 that, "There is not a composer who lived during his time or is alive today who was not touched, and sometimes transformed, by his work." Aaron Copland was heavily influenced by Stravinsky's rhythm and vitality. Contrarily, Stravinsky's music was not-well received by other composers of his time; Marc Blitzstein wrote that Stravinsky was just "not great enough," while Constant Lambert described L'Histoire du soldat as having "the drabbest and least significant phrases." Nonetheless, Stravinsky received many honours, including the Royal Philharmonic Society's gold medal, the Léonie Sonning Music Prize, the Wihuri Sibelius Prize, and the Portuguese Military Order of Saint James of the Sword. In 1998, Time magazine named Stravinsky one of the 100 most influential people of the century.