That is what we discovered on Wikipedia concerning the Zac & George:

Country music, also known as country and western or simply country, is a music genre known for its ballads and dance tunes, identifiable by both traditional lyrics and harmonies accompanied by banjos, mandolins, fiddles, harmonicas, and many types of guitar; either acoustic, electric, steel, or resonator guitars. Once called hillbilly music, the term country music was popularized in the 1940s to give it a correct term.

It originated in the Southern United States, and spread throughout the Piedmont area of United States, from Louisiana along the Appalachian Mountains to New York. The music is believed to be derived from British folk music, brought to the United States during early waves of immigration. Rooted in American folk music, such as old-time and Southern Appalachian music, many traditions blended to form country music. In particular, this included cowboy and vaquero Western music and African-American traditional folk songs and spirituals. Mexican, Irish, and Gospel music have had a formative influence on the genre, as have the Polynesian Hawaiian music and the Southwestern styles of New Mexico and Tejano, as well as gospel music, blues modes from blues music.

Country music has remained an integral part of the American music scene, with a recent revitalization in interest since the early 2020s. In 2023, 45% of Americans reported listening to country music, an uptick in the genre's popularity.