This is what we found on Wikipedia regarding the One Night In Nashville:

Country (also called country and western) is a music genre originating in the southern regions of the United States, both the American South and the Southwest. First produced in the 1920s, country music is primarily focused on singing stories about working-class and blue-collar American life.

Country music is known for its ballads and dance tunes (i.e., "honky-tonk music") with simple form, folk lyrics, and harmonies generally accompanied by instruments such as banjos, fiddles, harmonicas, and many types of guitar (including acoustic, electric, steel, and resonator guitars). Though it is primarily rooted in various forms of American folk music, such as old-time music and Appalachian music, many other traditions, including African-American, Mexican, Irish, and Hawaiian music, have had a formative influence on the genre. Blues modes from blues music have been used extensively throughout its history as well.

Once called "hillbilly music", the term country music gained popularity in the 1940s. The genre came to encompass western music, which evolved parallel to “hillbilly music” from similar roots, in the mid-20th century. Contemporary styles of western music include Texas country, red dirt, and Hispano- and Mexican American-led Tejano and New Mexico music, which still exists alongside longstanding indigenous traditions.

In 2009, in the United States, country music was the most-listened-to rush-hour radio genre during the evening commute, and second-most popular in the morning commute.