In the 1920s, a new style, called Swain, was invented, and from 1935 to 1945 it reached its peak, which spoke to the age of Swing.
A swinging group often has fourteen or fifteen musicians who are divided into three groups: saxophones (three to five players), brass winds (three or four trumpets and a trombone), and rhythm-guards (piano, bass, guitar and bass).
In the Swing band, melodies were often performed by all instruments. In this way, it was often necessary for you to rely more on regulated pieces than improvise. So a group with such a number of musicians needed pieces that were set and not written.
The Blue Skies piece by Fletcher Henderson and Benny Goodman’s band, one of the most popular pieces of the Swing Age.