When Copland turned to folk and popular music for inspiration, he launched the most productive period of his career. In 1935, he composed El Salón México, drawing on Mexican folk music to produce a new sound. He also began writing film scores, such as those for “Of Mice and Men” (1939), “Our Town” (1940), and “The Heiress” (1949). Ballet proved to be another creative outlet. In the early 40s, Copland composed two of his most famous: Rodeo, written in 1942 (the same year the US formally entered World War II), and the Pulitzer Prize-winning Appalachian Spring (1944). 

Appalachian Spring was the third and last of Aaron Copland’s “Americana” dances (after Billy the Kid and Rodeo.)  More introspective and lyrical than the previous “Western” works, Appalachian Spring was composed for Martha Graham. Copland noted that “the music of the ballet takes as its point of departure the personality of Martha Graham.” While the ballet’s working title was “Ballet for Martha,” the final iteration of its name, taken from a poem by Hart Crane, refers to a spring or brook in the Appalachian Mountains rather than the season. Edwin Denby summarized the ballet in the Herald Tribune:  

 . . . a pioneer celebration in spring around a newly built farmhouse in the Pennsylvania hills in the early part of the last century. The bride-to-be and the young farmer-husband enact the emotions, joyful and apprehensive, their new domestic partnership invites. An older neighbor suggests now and then the rocky confidence of experience. A revivalist and his followers remind the new householders of the strange and terrible aspects of human fate. At the end, the couple is left quiet and strong in their new house.  

Copland scored the original ballet for a chamber ensemble, subsequently arranging Appalachian Spring for full orchestra. It is in this form that the work is most famous. In his notes for the suite’s premiere in 1945, Copland described the eight sections as follows:   

• VERY SLOWLY. Introduction of the characters, one by one, in a suffused light.  
• FAST. Sudden burst of unison strings in A-major arpeggios starts the action. A sentiment both elated and religious gives the keynote to this scene. 
• MODERATE. Duo for the Bride and her Intended—scene of tenderness and passion.  
• QUITE FAST. The Revivalist and his flock. Folksy feelings—suggestions of square dances and country fiddlers.  
• STILL FASTER. Solo Dance of the Bride—presentiment of motherhood. Extremes of joy and fear and wonder.  
• VERY SLOWLY (as at first). Transition scenes reminiscent of the introduction.  
• CALM AND FLOWING. Scenes of daily activity for the Bride and her farmer-husband. There are five variations on a Shaker theme…sung by a solo clarinet… 
• MODERATE. CODA. The Bride takes her place among her neighbors. At the end, the couple is left “quiet and strong in their new house.” Muted strings intone a hushed, prayer-like passage. The close is reminiscent of the opening music.