U.S.A.
There really isn't much cultural music in America.
Rock and Roll(Elvis, Chuck Berry) and it's various forms like Beach Music(The Drifters), Death(Death) Southern(Allman Bros)' oh hell, take your pick

Blues(Delta, Texas, Chicago) - Bukka White, Son House, Rev. Gary Davis, B.B. King, Stevie Ray Vaughn....
Bluegrass - also called American Folk by some - Allison Krause and Union Station, Lester Flatt & Earl Scruggs, Doc Watson, The Carter Family,
Gillian Welch....
Jazz - Professor Longhair, Charlie Parker....
Zydeco - Buckwheat Zydeco, Michael Doucet & BeauSoleil, Russel Gordon & the Creol Untouchables...
Country and Western - although usually lumped together they are actually 2 distinct types of music with variations within each.
Country - Hank Williams, Patsy Cline, Willie Nelson....
Western - Bob Willis and His Texas Playboys, Asleep at the Wheel....
Swing - Count Basie, Tommy Dorsey, Lionel Hampton, Duke Ellington....
Native American - this is a hugh category with a lot of variations in it like powwow, traditional ,ceremonial - Robert Mirabal, James Ironshell, R. Carlos Nakai
America is a land of various cultures that has created it's own culture. Some people will say these styles started in other countries. These styles are American as created by Americans blending their unique histories together.
