Which new form of jazz became the most popular type of music during the War years

Swing music

Explanation:

Swing music, also known as swing jazz or simply swing, is a style of jazz that originated in the United States in the late 1920s, becoming one of the most popular and successful musical genres in the country during the 1930s. swing uses regular instruments in jazz, such as a rhythm section formed by piano, double bass and drums; metals such as trumpets and trombones; wind-wood instruments, such as saxophones and clarinets; and very occasionally, stringed instruments such as violin or guitar. The swing preferably uses medium and fast tempos, generalizes the melodic riffs and frees the role of the drummer from certain restrictions that it had had until then. The characteristic set of the style was the big band, also acquiring more and more importance the role of the soloist. They emphasize in this style musicians like Fletcher Henderson, Benny Goodman, Duke Ellington or Count Basie.