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

Context paragraphs:
Swing (dance): "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".  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.  Today, the most well-known of these dances is the Lindy Hop, which originated in Harlem in the early 1930s.  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.

John Philip Sousa: 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.  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.  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".

Barbara DuMetz: Barbara DuMetz (born 1947) is an American photographer and pioneer in the field of commercial photography.  When she began working in Los Angeles as a commercial photographer in the 1970s, very few women had established and maintained successful careers in the field, especially African American women.  Known for her work with African American celebrities, corporations and images of everyday life in African American communities.

Ragtime: Ragtime – also spelled rag-time or rag time – is a musical style that enjoyed its peak popularity between 1895 and 1918.  Its cardinal trait is its syncopated, or "ragged", rhythm.  The style has its origins in African-American communities in cities such as St. Louis.  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.  Hogan has also been credited for coining the term "ragtime".  The term is actually derived from his hometown "Shake Rag" in Bowling Green, Kentucky.  Ben Harney, another Kentucky native, has often been credited for introducing the music to the mainstream public.  His first ragtime composition, "You've Been a Good Old Wagon But You Done Broke", helped popularize the style.  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.  Ragtime composer Scott Joplin ("ca."  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.  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.

Think Tank (Blur album): Think Tank is the seventh studio album by the English rock band Blur, released in May 2003.  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).  The album expanded on the use of sampled rhythm loops and brooding, heavy electronic sounds.  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.

Scoutreach: The Scoutreach Division of the Boy Scouts of America emphasizes service to rural and urban areas and to minority populations.  The African American Focus works with African American populations in partnerships with the NAACP, various African American churches and other groups.  The Hispanic/Latino Focus includes the ¡Scouting - Vale La Pena!  emphasis for Hispanic youth that provides Spanish language resources such as handbooks, training material, and videos.  The Soccer and Scouting emphasis is a partnership with the National Soccer Coaches Association of America to provide alternatives for Cub Scout age Hispanic youth.  The Asian American Focus reaches out to Indo-Chinese American, Vietnamese American, Chinese American, and Korean American communities.  The Rural Scouting focus targets small communities and includes the American Indian Scouting Association in partnership with the Girl Scouts of the USA.

Zabriskie Tenant House: The Zabriskie Tenant House was a historic house of the American colonial architecture style called Dutch Colonial on Dunkerhook Road in Paramus, in Bergen County, New Jersey, United States, adjacent to the Saddle River County Park.  The Zabriskie family, who farmed much of the area to the east of the Saddle River (Passaic River), built the home to house their domestic workers.  It was one of the few structures left in New Jersey directly related to free African American communities in the state, and was a remnant of an African American Dunkerhook community that (until the early 20th century) included several homes and an A.M.E. Church.  The house was added to the National Register of Historic Places on July 24, 1984.

African Americans and birth control: The history of African American women and their participation in the birth control movement reflects a very conflicted set of ideals regarding African American women, the use of contraceptive practices and abortion.  Prominent historical figures debated whether African American communities would benefit from birth control or if birth control was another methodical scheme put in place to suppress the African American community.

Jazz: Jazz is a music genre that originated in African American communities of New Orleans, United States, in the late 19th and early 20th centuries, and developed from roots in blues and ragtime.  Since the 1920s Jazz Age, jazz has become recognized as a major form of musical expression.  It then emerged in the form of independent traditional and popular musical styles, all linked by the common bonds of African American and European American musical parentage with a performance orientation.  Jazz is characterized by swing and blue notes, call and response vocals, polyrhythms and improvisation.  Jazz has roots in West African cultural and musical expression, and in African-American music traditions including blues and ragtime, as well as European military band music.  Although the foundation of jazz is deeply rooted within the black experience of the United States, different cultures have contributed their own experience and styles to the art form as well.  Intellectuals around the world have hailed jazz as "one of America's original art forms".

Claudia Stack: Claudia Stack (born May 3, 1966), is an educator, writer, documentarian and film producer.  She is best known for her film productions, “Under the Kudzu” (2012) and “Carrie Mae: An American Life” (2015), both of which focus on schools that African American families helped to build during the segregation era.  Southern African American families built schools of many different kinds from Reconstruction through the 1950s.  Rosenwald schools form the most recognizable part of this school-building movement.  Rosenwald schools were schools that African American communities built in partnership with the Julius Rosenwald Fund, which from 1912 to 1932 helped to build almost 5,000 school buildings across the South.  For more information about Rosenwald schools, please see Rosenwald School Resources.

Supporting paragraphs: Ragtime John Philip Sousa
Answer: Ragtime