World War II and the Shrinking of the Ensemble

Essential Question

How did wartime restrictions and other factors cause popular music ensembles to shrink in size during the 1940s, helping to set the stage for the small “combos” of Rock and Roll?


In the 1930s and early 1940s, American popular music was dominated by Big Bands that played Swing, an energetic and danceable style of Jazz. Bandleaders including Glenn Miller, Benny Goodman, Duke Ellington, Count Basie, and others toured and recorded with ensembles that often featured upwards of fifteen instrumentalists, in addition to the vocalists who often contributed to the Big Band sound. The popularity of this music was unchallenged; in 1941, the year the United States entered into World War II, every song that reached No. 1 on Billboard’s best selling singles chart was recorded by a Big Band. But by the war’s end in 1945, the era of the Big Band had abruptly declined, with an entirely new class of solo singers and small combos dominating the Pop charts.

The onset of the war affected every area of American culture, including popular music. The size of the U.S. military expanded from under 2 million active duty personnel in 1941 to over 12 million in 1945, diminishing the number of qualified instrumentalists available to perform in civilian orchestras. Some professional musicians who entered the service continued to play in military ensembles, including Glenn Miller, who left his Big Band at the peak of their popularity to serve as an entertainer for the troops abroad. But with significantly fewer musicians available to perform stateside, many Big Bands were forced to reduce down to smaller ensembles.

In addition to shrinking band sizes, World War II affected the music business on a material level. Many musical instrument manufacturers temporarily converted their factories to produce military contracts, replacing production of new saxophones and pianos with jet engines and ammunition. And in 1942, the War Production Board imposed strict rations on shellac—the primary material used to press phonographs—curtailing the number of records that could be manufactured. These changes made it abundantly clear that the country’s first priority was to win the war, and until victory was declared, the music business was of a lesser priority.

Wartime rationing also fundamentally changed civilian life, as Americans were asked to reduce their usage of tire rubber, gasoline, and many other household goods. Posters reminded citizens of their responsibility more to the country than to themselves with phrases such as, “Millions of troops are on the move… Is YOUR trip necessary?” Leaders of Big Bands were also faced with significant travel restrictions, and were forced to reduce their touring schedules. And with over 12 million enlisted service men and women, the ensembles that managed to stay together suffered from a shortage of audiences able to purchase concert tickets.

But it wasn’t just the war that affected the music industry of that time. From 1942 to 1944, the American Federation of Musicians imposed a strike against the major record labels due to disagreements over royalty payments. Union musicians, including many who performed in Big Bands, were temporarily forbidden from recording new music. Singers, who were not represented by the musicians union, were not required to participate in the strike, resulting in an upturn in vocal-based recordings and the rise of solo vocal performers, including Frank Sinatra.

Along with vocalists, specialty music genres such as R&B and Country also sold well during the strike. These genres generally relied on smaller rhythm combos and fewer horns than were featured in Big Bands. Instead, drums, piano, bass, and guitar could cover a similar amount of musical space as a larger ensemble, but at a fraction of the size. This combination of shrinking bands, the rise of solo performers, and the increasing popularity of more marginal styles of music provided the seeds from which Rock and Roll would grow in the 1950s, as American youth moved away from the Big Band music of their parents towards a new sound all their own.

This lesson explores the transition from the Big Band era of the 1930s and 40s to the rise of smaller ensembles and featured singers in the years following World War II. Students will analyze and draw conclusions from primary sources including wartime rationing posters, archival photographs, and Billboard chart lists. Video clips featuring the music of Glenn Miller, Frank Sinatra, Nat King Cole, and other artists provide students with visual and musical evidence to discuss factors that led to the shrinking of popular music ensembles and the emergence of genres that inspired Rock and Roll artists in the 1950s.

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Upon completion of this lesson, students will:

  1. Know (knowledge):
    • The dominance of Big Bands in the late 1930s and 1940s, including bandleaders such as Glenn Miller and Benny Goodman
    • How World War II and rationing affected civilian life in the U.S., including the ability of Big Bands to tour and retain musicians
    • Effects of the 1942 musicians strike on the American recording industry, including the emergence of solo entertainers and small combo-based musical genres
  2. Be able to (skills):
    • Interpret and discuss the meaning of primary source materials, including World War II-era rationing posters, archival photographs, and Billboard chart lists