was a traditional American folk music group that recorded between 1927 and 1956. Their music had a profound impact on bluegrass, country, Southern Gospel, pop and rock musicians. They were the first vocal group to become country music stars; a beginning of the divergence of country music from traditional folk music. Their recordings of such songs as "Wabash Cannonball" (1932), "Will the Circle Be Unbroken" (1935), "Wildwood Flower" (1928), and "Keep on the Sunny Side" (1928) made them country standards. Country and bluegrass artists such as Loretta Lynn, Roy Acuff, Dolly Parton, Earl Scruggs, Chet Atkins, and Don Reno were heavily influenced by traditional Appalachian music. Artists such as Bob Dylan, Jerry Garcia, and Bruce Springsteen have performed Appalachian songs or rewritten versions of Appalachian songs. Cajun music Cajun music, an emblematic music of Louisiana, is rooted in the ballads of the French-speaking Acadians of Canada. Cajun music is often mentioned in tandem with the Creole-based, Cajun-influenced zydeco form, both of Acadiana origin. These French Louisiana sounds have influenced American popular music for many decades, especially country music, and have influenced pop culture through mass media, such as television commercials. Oklahoma and southern US plains Before recorded history American Indians in this area used songs and instrumentation; music and dance remain the core of ceremonial and social activities. "Stomp dance" remains at its core, a "call and response" form; instrumentation is provided by rattles or shackles worn on the legs of women. "Other southeastern nations have their own complexes of sacred and social songs, including those for animal dances and friendship dances, and songs that accompany stickball games. Central to the music of the southern Plains Indians is the drum, which has been called the heartbeat of Plains Indian music. Most of that genre traces back to the hunting and warfare that was a strong part of plains culture. During the reservation period, they frequently used music to relieve boredom and despair. Neighbors gathered, exchanged and created songs and dances. This is a part of the roots of the modern intertribal powwow. Another common instrument is the courting flute. Shape-note or sacred harp singing developed in the early nineteenth century as a way for itinerant singing instructors to teach church songs in rural communities. They taught using song books that represented musical notation of tones by geometric shapes that associated a shape with a pitch. Sacred harp singing became popular