John David “JD” Souther, known for his work as an artist, songwriter and actor, and his collaborations with artists including the Eagles, Linda Ronstadt and James Taylor, died peacefully at his home in New Mexico, according to a statement posted on his official website on Tuesday (Sept. 17). Souther was 78.

Souther forged a friendship with the Eagles’ Glenn Frey and would collaborate as a writer on many of the Eagles’ biggest hits, including “New Kid in Town,” “James Dean,” “Doolin-Dalton” and “Best of My Love.” Souther also co-wrote the Eagles’ 1979 hit “Heartache Tonight” alongside Frey, Bob Seger and Don Henley, and co-wrote Henley’s 1989 hit song “The Heart of the Matter.” Souther also wrote songs including Bonnie Raitt’s “Run Like a Thief,” and Ronstadt’s “Faithless Love” and “White Rhythm and Blues.” Souther and Ronstadt also collaborated together on songs including “Prisoner in Disguise” and “Hearts Against the Wind,” which was featured in the 1980 film Urban Cowboy starring John Travolta.

In the process, Souther became one of the foremost musical architects in the 1970s country-rock scene. Souther was born in Detroit and raised in Amarillo, Texas. He began recording with a local group in Texas known as The Cinders; the group would release a single on Warner Bros. as John David and the Cinders.

Souther made his self-titled debut in 1972, and then teamed with Chris Hillman and Richie Furay to release the album The Souther-Hillman-Furay Band. Souther followed with the 1976 solo album Black Rose, which included a collaboration with Ronstadt, “If You Have Crying Eyes.”

Souther’s most well-known solo hit came in 1979 with “You’re Only Lonely,” which reached No. 7 on the Billboard Hot 100. In 1981, Souther nearly notched another top 10 on that chart, as his collaboration with James Taylor, “Her Town Too,” reached No. 11 on the Billboard Hot 100.

In 2015, he released his final album, Tenderness, telling Billboard at the time, “I wanted simple melodies and really beautiful arrangements. I wanted a really nice landscape for these stories to play out in. I just wanted to drive a little more gently; Mario Andretti once said the ideal is to win the race at the slowest speed, meaning you protect the equipment. It’s smooth. Winning a race is about power, but it’s also about being smooth…I think I sang this album better than I’ve sung any album before,” he says. “I’m not singing licks and trying to do fancy things. I’m just singing the melody; it seems to tell the story better. I didn’t have to strain. It didn’t tempt me to sing a bunch of licks or to oversing or sing too loud. Linda Ronstadt always tells me to pronounce the words, and she’s right. It makes a big difference. It gives the song more truth.”

As an actor, Souther appeared in movies including My Girl 2, Deadline and Postcards From the Edge, and in television series including Thirtysomething, Purgatory and a recurring role on Nashville.

Souther was honored with one of songwriting’s highest honors, induction into the Songwriters Hall of Fame, in 2013.

“It’s been said that JD Souther could have been a major artist if he had kept more of those beautiful, introspective songs he wrote for himself,” Kyle Young, CEO of the Country Music Hall of Fame and Museum, said in a statement. “He had the aching tenor voice, the good looks that got him TV acting jobs. But he was happy to co-write ‘New Kid in Town’ and ‘Best of My Love’ with his friends the Eagles and give ‘Prisoner in Disguise’ to Linda Ronstadt. He wasn’t a star of country-rock, but he was crucial to its enduring power.”

Souther had been set to launch a new tour with Karla Bonoff on Sept. 24 in Phoenix. Souther is survived by two sisters, his former wife and her daughter, as well as his dogs Layla and Bob, as well as many colleagues within the music community.

Donations in Souther’s honor can be made to the Best Friends Animal Society.