After centuries of percolating in America’s immigrant and racial mix, particularly in the American South, what was first called “hillbilly music” begins reaching more people through the new technologies of phonographs and radio.

During the Great Depression and World War II, country music thrives and reaches bigger audiences. Gene Autry sets off a craze for singing cowboys, Bob Wills adapts jazz’s Big Band sound to create Texas Swing, and Roy Acuff becomes a star.

Country music adapts to the cultural changes of post-war society. Bill Monroe and Earl Scruggs transform string band music into Bluegrass. Out of the bars comes a new sound and songs about drinking, cheating, and heartbreak: Honky Tonk.

In Memphis, the confluence of blues and hillbilly music at Sun Studios gives birth to “rockabilly,” the precursor of rock and roll. Elvis Presley and Johnny Cash are at the forefront. Nashville has become Music City USA.

During a time of upheaval, country music reflects the changes in American society. Loretta Lynn performs songs that speak on behalf of women. Charley Pride becomes a country star. Merle Haggard becomes the “Poet of the Common Man.”

With the Vietnam War intensifying, America is more divided than ever. Country music is not immune to the divisions. Kris Kristofferson abandons his military career, becomes a writer whose lyricism sets a new standard for country songs.