It’s intriguing to speculate how the history of music in the last century would have been altered if the extraordinary ballet impresario Serge Diaghilev had not decided to gamble on the young, relatively unknown Stravinsky. Diaghilev’s Ballets Russes—which the émigré Russian had established in Paris—was just starting to take the West by storm, and Diaghilev wanted a splendid new production for the climax of its season in 1910. His initial plans for better-known composers fell through, so Diaghilev, on a hunch, gave the commission to Stravinsky, then in his late 20s. It was a risk for everyone concerned, since The Firebird would be the first production by the emerging ballet company to feature an entirely new score.  Stravinsky was handed a scenario (devised in part by choreographer Michel Fokine) that drew on old Russian folklore. The Firebird tells of the downfall of a powerful, ogre-like figure of evil, Kastchei the Deathless, who seizes young princesses as captives while turning the knights who arrive to rescue them into stone. The protagonist Crown Prince Ivan enlists the Firebird, so called for her beautiful feathers that glitter and flicker like flames, to help destroy Kastchei and free his victims.   You can readily hear how Stravinsky’s own imagination must have caught fire (he even set aside his work on a bird of a different feather—the fairy-tale opera The Nightingale) when he took up Diaghilev’s invitation. The Firebird’s score blends the orchestral wizardry Stravinsky had learned as a student of Rimsky-Korsakov with the vitality of Russian folk music to yield a dazzling, evocative atmosphere. Throughout his later career, Stravinsky remained especially fond of The Firebird, returning to create three concert versions that he himself conducted tirelessly (a savvy financial move on the composer’s part). The most popular is the second of these suites, introduced in 1919, which uses less than half of the original ballet score and simplifies some of its orchestration.  The Firebird’s musical language shifts between chromatic gestures to illustrate the supernatural dimension (including a powerful non-Western scale that would later feature in The Rite of Spring’s harmonic vocabulary) and the singsong simplicity of folk song for the mortals. The suite opens with a spooky conjuring, low in the strings, of Kastchei’s magical realm. In his illusory garden, Prince Ivan encounters the Firebird, which is depicted with opulent colors and radiant trills. (Diaghilev spared no expense in the similarly gorgeous costumes Léon Bakst designed for this creature.) A calmly pastoral section follows, featuring Stravinsky’s already characteristically imaginative scoring for woodwinds. Prince Ivan observes the princesses who have been captured by Kastchei performing their ritual Khorovod, or round dance, and falls in love with the one destined to be his bride.  To protect Ivan, the Firebird casts a spell over Kastchei and his monstrous aides. Whipped into motion by Stravinsky’s frenetic rhythms, they are compelled to dance themselves to exhaustion in a savage “Infernal Dance.” Their paroxysms subside, while a serene lullaby (“Berceuse”) lulls the hypnotized Kastchei to sleep, its lazy tune first given by the bassoon. Ivan is instructed to destroy the giant egg containing the ogre’s soul, and Kastchei’s power vanishes. A solo horn, intoning the score’s most famous folk tune, announces the joyful arrival of sunlight. Together with Ivan and his betrothed, the rescued captives celebrate with music that swells and rings out in glorious triumph. The Firebird clearly shows Stravinsky on the cusp of a new world, mixing the orchestral mastery of his Russian mentors with the rhythmic vitality of the revolutionary about to burst out of his shell.