Country and Western was a type of music developed on Earth in the pre-Diaspora era.
In 1903 PD, when Admiral Raoul Courvosier of the Star Kingdom of Manticore heard music from Grayson for the first time, he compared it to Country and Western with an undertone of dislike. (HH2)
One popular Country & Western song was Mammas, Don't Let Your Babies Grow Up to Be Spacers. (HH9)