As rock 'n' roll evolved in the ‘60s, it began to shed its roots in country music in favor of the blues. But as the ‘70s loomed, they were brought back together and would soon go on to reach great new heights, both commercially and artistically.

The genres gravitated back toward each other quite naturally in the late ‘60s. Countrypolitan, the term given to the lush, string-laden records that were being made in Nashville, was starting to make inroads into the mainstream thanks to such names as Conway Twitty, Tammy Wynette and Charlie Rich.

Johnny Cash, part of the Million Dollar Quartet that popularized rockabilly at Sun Records in the mid-‘50s, had turned his career around on the strength of the remarkable 1968 live album, At Folsom Prison. Glen Campbell, who played guitar on dozens of rock songs as a member of the Los Angeles collection of session musicians known as the Wrecking Crew, even became a multimedia star – branching out into television and film – thanks to crossover hits like “By the Time I Get to Phoenix,” “Wichita Lineman” and “Galveston.”

At the same time, the Los Angeles folk-rock scene had gotten together in a Hollywood Hills neighborhood called Laurel Canyon. David Crosby, Stephen Stills and Graham Nash first sang together in Joni Mitchell’s living room during a party there. It was bound to happen eventually: Crosby had brought Mitchell, who was dating Nash, to L.A. to produce her debut. Stills and Crosby were mainstays on the scene when they had been members of, respectively, Buffalo Springfield and the Byrds. Mitchell knew another ex-member of Buffalo Springfield, Neil Young, from their days on the Canadian folk circuit. And it welcomed newcomers, particularly at the Troubadour in nearby West Hollywood, where the open-mic night on Mondays gave everyone a chance to hear what their friends and peers were working on.

“My very first day in California,“ Detroit native Glenn Frey recalled in Vanity Fair’s oral history of the scene, “I drove … to Laurel Canyon, and the first person I saw standing on the porch at the Canyon Store was David Crosby. He was dressed exactly the way he was on the second Byrds album — that cape, and the flat wide-brimmed hat. He was standing there like a statue. And the second day I was in California I met J. D. Souther.”

Frey and Souther eventually became roommates in Echo Park, where their downstairs neighbor was Jackson Browne, and formed a folk-country duo called Longbranch Pennywhistle. They released an album in 1969, but split up a couple of years later when their label, Amos Records, went out of business.

Listen to 'Rebecca' by Longbranch Pennywhistle

Destiny would soon strike in the form of Souther’s girlfriend, Linda Ronstadt, who was establishing a solo career after breaking out with the Stone Poneys in 1967 with “Different Drum.” Needing a band for a tour in 1971, Ronstadt hired Frey as a guitar player and the Texas-born drummer from another former Amos act called Shiloh, Don Henley. The musical chemistry between Henley and Frey was instant, and while on the road, they decided to form a band, with Ronstadt giving them her blessing.

The tour ended, but Ronstadt had a gig at Disneyland coming up in July. For that date, Henley and Frey were rounded out by two men who had considerable experience with country-rock: Bernie Leadon, who had been in the Flying Burrito Brothers, and bassist Randy Meisner from Poco. The Eagles were born.

Meanwhile, manager David Geffen was trying to get Browne, his client, signed. Ahmet Ertegun at Atlantic Records wasn’t interested, but suggested that Geffen start his own label and was willing to help fund and provide distribution through Atlantic. With his partner, manager Elliot Roberts, Geffen created Asylum Records and quickly snapped up virtually all of the talent in the area. In addition to Browne, they signed the Eagles, Mitchell, Ronstadt, Souther and another singer-songwriter from the Troubadour scene, Tom Waits, within the next year.

Browne’s debut hit the streets in January 1972 and gave him a Top 10 hit right out of the gate with “Doctor My Eyes.” But another of Roberts' clients, who was already signed to Reprise, would arguably make the era's definitive combination of country and rock. The success of Crosby, Stills & Nash proved that there was a market for mostly acoustic bands that could harmonize. Within a few years, groups like America, Seals & Crofts, Bread and Loggins & Messina were charting, with many of their songs helping to create a new sub-genre labeled soft rock.

As a member of Buffalo Springfield and Crosby, Stills, Nash & Young, as well as a solo artist, Young had been experimenting with country sounds for six years. But the release of Harvest in February 1972 was a full immersion into the genre. Most of its 10 songs were cut in Nashville with a collection of session pros that Young dubbed the Stray Gators, and the instrumentation, in particular Ben Keith’s pedal steel guitar, suited the melancholy found in Young’s songs. Harvest and its lead single, “Heart of Gold,” reached No. 1, and the country-rock explosion had begun.

That summer, the Eagles’ first album -- which featured three Top 40 hits in "Take It Easy,” “Witchy Woman” and “Peaceful Easy Feeling” -- came out. They doubled down on country-rock for their next effort, creating a concept album built around themes from the Old West.

Desperado went so far as to see the Eagles dressing up like the mythical outlaws the Dalton Gang on the cover. The title track and “Tequila Sunrise” would eventually become among their best-loved songs, but the album failed to capitalize on the commercial success of Eagles – stalling at No. 41 – possibly because, according to Henley, people had a tough time accepting that the group were outlaws.

"The metaphor was probably a little bulls---,” he said in Barney Hoskyns’ Hotel California: The True-Life Adventures of Crosby, Stills, Nash, Young, Mitchell, Taylor, Browne, Ronstadt, Geffen, the Eagles and Their Many Friends. “We were in L.A. staying up all night, smoking dope, living the California life, and I suppose we thought it was as radical as cowboys in the Old West.”

Listen to Linda Ronstadt's 'Love Has No Pride'

Despite her early success with the Stone Poneys, Ronstadt’s solo career didn’t take off until her fourth record, 1973’s Don’t Cry Now, which gave her a couple of modest hits in “Love Has No Pride” and “Silver Threads and Golden Needles,” the latter of which hit the Top 20 on Billboard’s country chart.

But her next effort and last for Capitol Records, Heart Like a Wheel, turned her into a superstar, topping the album chart and going double-platinum on the strength of the singles “You’re No Good” and “When Will I Be Loved.” Ronstadt would ride out the decade as one of the most popular singers, with her next five albums hitting the Top 5. Her records all blended covers of rock, country and soul chestnuts with new compositions by the top talent in L.A., giving valuable exposure to songwriters like Souther, Warren Zevon and Karla Bonoff.

The sense of community was exemplified by the consistency of the grooves. The Eagles were a self-contained unit, but for the others, the cream of L.A. session musicians -- including the "Mellow Mafia" of Danny Kortchmar (guitar), Lee Sklar (bass), Craig Doerge (keyboards) and Russ Kunkel (drums) -- were called in. And they also frequently played on each other's records, as did their friends James Taylor, Joni Mitchell and the individual members of Crosby, Stills & Nash.

That camaraderie carried over into their private lives too. “It was a scene with incredibly talented, attractive people,” Geffen told Vanity Fair. “And many of them had sex with one another. Who wouldn't? It was after birth control and pre-AIDS. It was a different world.”

The Eagles quickly rebounded from Desperado in 1974 with On the Border, where they fought with producer Glyn Johns, who’d also helmed their first two LPs. “I didn’t mind him pointing us in a certain direction,” Frey told Cameron Crowe in Rolling Stone. “We just didn’t want to make another limp-wristed L.A. country-rock record. They were all too smooth and glassy. We wanted a tougher sound.”

To achieve this, they replaced Johns with Bill Szymczyk after only a few songs had been recorded and added a third guitarist, Don Felder, who played on only one of On the Border’s tracks, but it would be a significant one. With “Already Gone,” the Eagles hit the blend of rock guitar crunch and soaring country harmonies they’d been after since the beginning. Still, one of the songs recorded with Johns, the countrified “Best of My Love,” became their first No. 1 hit.

Felder’s arrival, followed by Joe Walsh, who replaced Leadon for 1976’s blockbuster Hotel California, would solidify their credentials as a rock band, but the country influence was still present on later hits like “Lyin’ Eyes,” “New Kid in Town” and “Heartache Tonight.” As Frey told Crowe, they achieved their massive success not just because of their talent, but also ecause they had done their homework.

“We had it all planned," he noted. "We’d watched bands like Poco and the Burrito Brothers lose their initial momentum. We were determined not to make the same mistakes. This was gonna be our best shot. Everybody had to look good, sing good, play good and write good. We wanted it all. Peer respect. AM and FM success. No.1 singles and albums, great music and a lot of money.”

Listen to Gram Parsons and Emmylou Harris Sing 'Return of the Grievous Angel'

After being fired from the Flying Burrito Brothers, Gram Parsons embarked on a solo career. He recruited some country-rock veterans, including some members of Elvis Presley’s TCB Band, and found a young folksinger with an ethereal voice, Emmylou Harris, to bring his vision of “Cosmic American Music” – a blend of rock, country, soul and folk – to fruition. GP arrived in early 1973. But Parsons died of a drug overdose on Sept. 19, 1973, at the age of 26.

A second album, 1974’s Grievous Angel, was compiled from songs he recorded shortly before his death of a drug overdose. Those five albums Parsons recorded – with the Byrds, the Burrito Brothers and as a solo act – didn’t sell particularly well, but they all exerted tremendous influence over subsequent generations of musicians.

Despite his early Top 10 success, it took a little longer for Browne to become a superstar. It wasn’t until his fourth album, 1976’s The Pretender, that he hit the Top 10 on the Billboard album chart. But the follow-up, Running on Empty, sent him into the same territory as his comrades. It was a live album about being on the road, complete with songs recorded backstage, in hotel rooms and on the tour bus. The hit title track perfectly reflected the mindset of Baby Boomers who were experiencing burnout in the post-hippie era. Browne continued to have hits through 1986’s Lives in the Balance.

Oddly, the man who was arguably the linchpin of the Laurel Canyon scene, Souther, had the least amount of success in the public eye. Although he co-wrote a slew of the Eagles’ biggest hits, he put out solo albums intermittently at a time when his friends were releasing records more or less annually. His three albums in the ‘70s resulted in one hit, 1979’s “You’re Only Lonely.”

Listen to J.D. Souther's 'You’re Only Lonely'

The mid-‘70s apex of country-rock also opened the doors for country music to enter the mainstream with an unprecedented degree of popularity. Countrypolitan had now evolved into a type of soft rock that fit in perfectly at adult contemporary radio. Dolly Parton had been placing songs on the country chart for a decade when “Here You Come Again” hit No. 3 on the Hot 100 in 1977 and turned her into a household name. Over the next few years, Kenny Rogers, Crystal Gayle, Willie Nelson and many others regularly punctuated the pop and adult contemporary charts.

This extended beyond music. The Dukes of Hazzard, with Waylon Jennings contributing the theme song and narration, averaged 19 million television viewers in its first five seasons. Loretta Lynn saw her autobiographical 1970 song “Coal Miner’s Daughter” turned into a film (with the Band’s Levon Helm playing her father). Parton and Kris Kristofferson, who was a janitor in Columbia’s Nashville studio when Bob Dylan recorded Blonde on Blonde before he wrote Janis Joplin’s “Me and Bobby McGee,” became movie stars.

But on the rock side, it was collapsing from within by 1980. The Eagles imploded due to acrimony and drug use, and although Henley and Frey embarked on successful solo careers, their sound was more in line with what was on the pop charts at the time than, say, “Tequila Sunrise” or “Best of My Love.”

Ronstadt decided to try Broadway, starring in a production of Gilbert and Sullivan’s 19th-century comic opera The Pirates of Penzance and its film adaptation. She then released three albums of standards with the Nelson Riddle Orchestra, What’s New, Lush Life and For Sentimental Reasons. She returned to her country roots in 1987, joining Parton and Emmylou Harris for the smash Trio.

For the bulk of the ‘80s, there was little cross-pollination between the genres, although it occasionally popped up. In 1981, a time when traditional country couldn't have been less hip in the rock world, Elvis Costello, the quintessential critics’ darling, went to Nashville and recorded Almost Blue, a collection of country covers that was produced by the architect of the countrypolitan sound, Billy Sherrill.

Despite his punk and New Wave credentials, Costello's love of country music was sincere. He was turned on to the genre by the Parsons' and Byrds’ 1968 classic Sweetheart of the Rodeo. “At first, it was a lot to take in,” he told Nashville Scene. “And then I started to really listen to the songs and started to get curious — like, ‘Who are these Louvin Brothers? Who is this Merle Haggard?’ I knew who Johnny Cash was — but truthfully, most of the hits I knew on the radio were kind of novelty songs. The deep songs weren't as well-known to people of my age. Once I started to hear 'I Still Miss Someone' and these other songs — goodness, it was just the same as discovering James Carr or some great soul singer, you know? It was really a door opening.”

Almost Blue was released with a warning sticker on the packaging that said, “This album contains country & western music and may produce radical reaction in narrow-minded people.” No kidding. Almost Blue became the lowest-charting album of Costello's career to that point. Still, he’s returned to country periodically since then, most notably on King of America (1986), The Delivery Man (2004), Secret, Profane & Sugarcane (2009) and National Ransom (2010).

Watch Elvis Costello Sing 'I’m Your Toy'

After exploring other musical paths for more than a decade, Young returned to a country-infused sound in 1983 on an album he called Old Ways. But his label, Geffen, wanted a rock album and refused to put it out. Young countered with Everybody’s Rockin’, which had a rockabilly feel to it. Both sides sued each other, and, after it was settled, a different version of Old Ways was released in 1985. As with Costello and Almost Blue, it failed to catch an audience outside his most die-hard fans, and reached only No. 75.

The closest country and mainstream rock came to each other in the ‘80s was the casually named sub-genre of heartland rock. Although Bob Seger made his name as a white soul belter, he had one of the biggest hits of his career in 1983 with “Shame on the Moon,” which was written by country star Rodney Crowell.

By the middle of the decade, heartland rock was less about country instruments and rhythms and more about incorporating southern or rural settings in its lyrics. Tom Petty and the Heartbreakers' Southern Accents, which was released in 1985, was originally intended as a double-LP about the South. The concept was never fully realized, but some of the songs written with the theme in mind -- including “Rebels,” “Spike” and the title track -- were among its highlights.

Another record from 1985, Scarecrow, saw John Mellencamp grow as a songwriter by examining the effect of Reaganomics in his home state of Indiana. Two years later on the follow-up The Lonesome Jubilee, he scaled back the electric guitars in favor of fiddle, banjo, accordion, mandolin and autoharp. His excursions into folk and country stopped after 1989’s Big Daddy, but all three albums reached the Top 10 and yielded a combined seven Top 20 singles.

Still, outside of the Georgia Satellites and their 1986 honky-tonk-ready hit “Keep Your Hands to Yourself,” it became harder and harder for new acts to fuse the genres and be heard by a rock audience. The depictions of small-town blue-collar life on country singer-songwriter Steve Earle’s first few albums in the mid-‘80s drew favorable comparisons to Bruce Springsteen (whose “State Trooper” he regularly covered in concert), but he couldn’t break through to a bigger audience apart from a few songs on the Mainstream Rock chart. And Earle still fared better than the well-reviewed first two albums by the Kentucky Headhunters.

Listen to Uncle Tupelo's 'Graveyard Shift'

Country-rock didn’t disappear entirely. Instead, it moved underground, where bands like Jason and the Scorchers, the Long Ryders and Lone Justice continued what Parsons and Young did a decade earlier, but they added the raw energy of punk to their music. Even X, one of the leaders of L.A.’s punk scene, moved in that direction when they added Dave Alvin of the Blasters to their lineup.

The sound was originally given the name of cowpunk, but it eventually picked up the name “alternative country.” By the early ‘90s, it had become a genuinely viable sub-genre, with Uncle Tupelo, the Jayhawks and the Bottle Rockets signing major label deals. And as he was being hailed as the “Godfather of Grunge,” Young reunited the Stray Gators and released the long-promised sequel to Harvest, Harvest Moon.

These days, alternative country generally goes by the broader name of Americana, which acknowledges the influence of African-American musicians on the music. Had Parsons lived, he’d see his work reflected in the music of Jason Isbell, Lucinda Williams, the Lone Bellow and Sturgill Simpson.

“I think genres are actually disappearing, more and more,” Parsons' protege Harris, who became a successful solo artist, told Pitchfork in 2008. “Is there really rhythm & blues, is there really country music? More and more young artists are dipping into the pool of all these various forms of music and coming up with something that's totally new themselves. Fortunately, we'll always have the genre in their pure form, to go back to and to learn from and to steal from. To add to our stew."

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