Final answer:
Louis Armstrong formed the small-band format 'Louis Armstrong and His All Stars' in 1947, which he led for the rest of his life. As a major jazz figure and improviser, his influence remains significant in music today.
Step-by-step explanation:
After fronting a big band for more than fifteen years, Louis Armstrong returned to a small-band format in 1947 with the formation of Louis Armstrong and His All Stars, the unit he would lead for the rest of his life. Louis Armstrong, a seminal jazz musician, was a pivotal figure in the Harlem Renaissance and is often referred to as the "most important improviser" in the history of jazz. His trademark raspy sounding voice and mastery of improvisation greatly influenced the music scene. Armstrong's legacy and influence extend well into the 21st Century, impacting jazz and contemporary music alike.
In the context of the given information, Figure 1 and Figure 24.15 highlight the popularity of black jazz bands like the King and Carter Jazzing Orchestra among urbanites in the 1920s, which parallels the significant impact that Armstrong had on music and culture during his time.