Swing jazz would have its beginnings in the late 1920s, not coming out fully until the early to mid-30s. It would reach its peak during the 40s, followed by a quick and steady decline into the shadows by the 50s. There it remained until around 1990 when it started regaining a following.
The Jazz Age -- the 1920s -- among other things, was marked by dixieland and hot jazz bands, the flapper, the Charleston, the creation of Lindy Hop, and the very beginnings of swing jazz music.
Between 1900 and 1920, the more common early types of American music included concert bands and Dixieland -- an early style of jazz. These early types were distinguished by their ensemble playing, and out of which developed the hot jazz bands of the mid to late 20s. These hot jazz bands, with the help of Louis Armstrong, would evolve into swing jazz music of the 30s.
Changes that marked the introduction of swing jazz included the use of a more free flowing rhythm using four beats to a bar instead of the two beats that was common in New Orleans dixieland jazz. The rhythm itself would be supplied by a piano and/or a set of drums or an occassional guitar. The tuba of the older styles was replaced by a string bass.
Another change was the common use of riffs, or short melodic ideas that were used repeatedly in call-and-response patterns between instrumental sections of a band. The sections were often composed of a brass section such as trumpets and trombones; and a reed section with instruments such as the saxophone and the clarinet. The call-and-response style was much in imitation to call-and-response style found in the African-American Southern Baptist churchs.
Many of the early swing jazz bands grew to have 16 or more instruments playing with and against each other. At this point, many of these swing jazz big bands rightly referred to themselves as orchestras.
There were different styles of swing jazz. There were the hot bands, such as Count Basie and Tommy Dorsey, which often played quick hard-driving jump tunes. There were also the sweet bands, such as the Glenn Miller Orchestra, who played less improvised tunes with more emphasis on sentimentality. In general, hot tunes were fast-paced, sometimes heart-racing songs, while the sweet tunes were the slower-paced, often heart-felt songs. This is what Duke Ellington alludes to in the song "It Don't Mean a Thing (If It Ain't Got That Swing)" when he writes "It don't matter if you play it sweet or hot."
With swing jazz, band members were given more opportunities to solo during a song, becoming more visible, and even to gain a following of fans. Some players, such as drummer Gene Krupa, would use such fame to start bands of their own.
The role of the band leader also changed. Bandleaders use to stand in front of the band and wave a baton, such men as Paul Whiteman. With swing jazz, the bandleader often played an instrument as well, such as during a solo such as clarinet playing bandleader Benny Goodman, or throughout the song like piano player bandleader Count Basie.
Often, music will influence the way a dance evolves. However, with swing jazz, it may have been the other way around. The bands playing to live dancing audience would tailor the music for the dancer's benefit. Quickly, the music evolved to fit the dancing, creating a symbiotic relationship between the two so great, they are referred to by the same term: "swing."