Robert Knight, who was the first to have a hit with the chestnut "Everlasting Love," passed away on Sunday at the age of 72. No cause of death was revealed, only that it was a "short illness."

"Robert was just a great guy and very gentle man," Mac Gayden, the song's co-writer, told the Tennessean, where the news broke.

Knight was born Robert Peebles in Franklin, Tenn., a suburb of Nashville, on April 24, 1945. As a teenager, he and his friends, calling themselves the Paramounts, had a minor hit in 1961 with "Free Me." But, as Billboard notes. he soon opted for college, studying chemistry at Tennessee State University and singing with the Fairlanes.

In 1967, he was performing at a fraternity party at Vanderbilt University, where he met Gayden, who owned Rising Sons Music along with his writing partner Buzz Cason. They signed Knight as a solo artist and began to make a record. The last song of the session was "Everlasting Love," which they considered to be "kind of like a throwaway tune." Knight would have to do some work on it to make it fit his style.

“Buzz and Mac were country artists, and I was R&B, and so I had to make it more of an R&B song,” he told Rebeat in 2016. “I practiced and practiced on it. It was a hard song to sing because, at the time, it was hard to sing a fast song slow. I didn’t sing it the way they had written it. I made some changes to fit my voice, and I didn’t do it note for note. They had the melody going too fast, and it was jamming. It wasn’t doing right; it wasn’t sounding right. So, I started what you call a steady step. I start singing a beat and a half: ‘hearts-go-a-stray’ – like that. It wasn’t like that in the beginning, and I think that’s what got ‘Everlasting Love’ off the ground.”

The song reached No. 13 on the Billboard Hot 100 and No. 14 at R&B. A year later, it was turned into a No. 1 U.K. hit by the Love Affair. But the biggest U.S. success for the song came from Carl Carlton, who took it to No. 6 in 1974. U2 released it as the b-side of "All I Want Is You" in 1989, and Gloria Estefan's 1994 version peaked at No. 27 on the Hot 100 and topped the Hot Dance Club Play.

"With 'Everlasting Love,' Knight created the blueprint for one of the most famous, most enduring songs to ever come out of Music City," Michael Gray, a historian at the Country Music Hall of Fame and Museum, said. "Recording extensively with Mac Gayden and Buzz Cason in the 1960s, Robert was working in integrated bands when it was still taboo to do so in some places. The original version of 'Everlasting Love' is a prime example of the successful musical exchange between black and white musicians during a decade of great racial upheaval and Civil Rights struggles in the South."

Knight had two other minor hits, "Blessed Are the Lonely" and "Isn't It Lonely Together." After leaving the music industry, Knight worked at Vanderbilt as a lab technician and on the grounds crew.

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