Question: Which popular music style was a modification of the marches from "The March King" with heavy influences from African American communities?

<P0-S0> Think Tank is the seventh studio album by the English rock band Blur, released in May 2003. <P0-S1>  Jettisoning the Britpop sound of Blur's early career as well as the lo-fi indie rock of "Blur" (1997), "Think Tank" continued the jam-based studio constructions of the group's previous album, "13" (1999). <P0-S2>  The album expanded on the use of sampled rhythm loops and brooding, heavy electronic sounds. <P0-S3>  There are also heavy influences from dance music, hip hop, dub, jazz, and African music, an indication of songwriter Damon Albarn's expanding musical interests. <SEP> <P1-S0> John Philip Sousa ( ; ; November 6, 1854 – March 6, 1932) was an American composer and conductor of the late Romantic era, known primarily for American military and patriotic marches. <P1-S1>  Because of his mastery of march composition, he is known as "The March King", or the "American March King" due to his British counterpart Kenneth J. Alford also being known by the former nickname. <P1-S2>  Among his best-known marches are "The Stars and Stripes Forever" (National March of the United States of America), "Semper Fidelis" (Official March of the United States Marine Corps), "The Liberty Bell" (used as the theme for Monty Python's Flying Circus), "The Thunderer" and "The Washington Post". <SEP> <P2-S0>  The style has its origins in African-American communities in cities such as St. Louis. <P2-S1> Ragtime – also spelled rag-time or rag time – is a musical style that enjoyed its peak popularity between 1895 and 1918. <P2-S2>  Its cardinal trait is its syncopated, or "ragged", rhythm. <P2-S3>  Ernest Hogan (1865–1909) was a pioneer of ragtime and was the first composer to have his ragtime pieces (or "rags") published as sheet music, beginning with the song "LA Pas Ma LA," published in 1895. <P2-S4>  Hogan has also been credited for coining the term "ragtime". <P2-S5>  The term is actually derived from his hometown "Shake Rag" in Bowling Green, Kentucky. <P2-S6>  Ben Harney, another Kentucky native, has often been credited for introducing the music to the mainstream public. <P2-S7>  His first ragtime composition, "You've Been a Good Old Wagon But You Done Broke", helped popularize the style. <P2-S8>  The composition was published in 1895, a few months after Ernest Hogan's "LA Pas Ma LA." Ragtime was also a modification of the march style popularized by John Philip Sousa, with additional polyrhythms coming from African music. <P2-S9>  Ragtime composer Scott Joplin ("ca." <P2-S10>  1868–1917) became famous through the publication of the "Maple Leaf Rag" (1899) and a string of ragtime hits such as "The Entertainer" (1902), although he was later forgotten by all but a small, dedicated community of ragtime aficionados until the major ragtime revival in the early 1970s. <P2-S11>  For at least 12 years after its publication, "Maple Leaf Rag" heavily influenced subsequent ragtime composers with its melody lines, harmonic progressions or metric patterns. <SEP> <P3-S0> "Swing dance" is a group of dances that developed with the swing style of jazz music in the 1920s-1940s, with the origins of each dance predating the popular "swing era". <P3-S1>  During the swing era, there were hundreds of styles of swing dancing, but those that have survived beyond that era include: Lindy Hop, Balboa, Collegiate Shag, and Charleston. <P3-S2>  Today, the most well-known of these dances is the Lindy Hop, which originated in Harlem in the early 1930s. <P3-S3>  While the majority of swing dances began in African American communities as vernacular African American dances, some swing era dances, like Balboa, developed outside of these communities.