In the 1960s, while the Vietnam War was underway and counter-culture movements and anti-war sentiments pervaded, the U.S. witnessed a shift in music. This tends to happen during monumental changes in society. Country music was borrowing from rock and roll, and rock musicians were borrowing from country. That's the basic foundation of country rock—a bit of twang to soften the hard edges of rock and roll achieved by the addition of pedal steel, lap steel, fiddle, mandolin, and often harmonies.
Stemming mostly from Nashville and Southern California, country rock was pioneered by artists like Gram Parsons, Buffalo Springfield, the Byrds, Ricky Nelson, and even Bob Dylan. Of course, Neil Young - a founding member of Buffalo Springfield - played a big role in shaping the genre in his solo music as well. In northern California, the Grateful Dead and Creedence Clearwater Revival embraced country sounds in their own way. Nashville legends like Johnny Cash and Emmylou Harris also pivoted towards rock in the 1970s while maintaining their country core. It took fans on both sides of the spectrum some time to latch on, but eventually, the genre found its fans.
The Southern California hippies weren't just cosplaying as country artists. There was an authentic effort made by many in the rock world to appreciate, understand, and pay tribute to the country artists who shaped their early desire to pursue music. You could say that country rock was simply born from experimentation. These musicians initially gravitated towards rock and later wanted to incorporate elements from earlier influences. Experimentation is at the core of musical evolution.
While the country rock scene peaked in the mid to late '70s, the genre lived on in impact and influence. Steve Earle championed country rock throughout the '80s and '90s with landmark albums like Guitar Town and Copperhead Road. Spinoffs from the country rock scene like The Blasters and Los Lobos were early influences on Dwight Yoakam's legendary career in 1980s Los Angeles. The genre also left its mark on the alternative country movement in the early '90s, with Uncle Tupelo (Jay Farrar and Jeff Tweedy) drawing from both the Carter Family and '80s punk. Son Volt and Wilco (also Jeff Tweedy) would later carry on the torch with artists like The Black Keys, Old 97s, and Hank III coming along. And of course, the combo of country and rock live on through superstars Kacey Musgraves, Sturgill Simpson, and Jason Isbell.