Elton John, who was a close friend of Diana’s, was asked to sing at her funeral service at Westminster Abbey six days later. He reached back to a classic he and his lyricist, Bernie Taupin, had written in 1973 as a tribute to Marilyn Monroe — another world-famous blonde who had died at the age of 36.

In the days leading up to the funeral service, Taupin revised the lyric. The sad, wistful tone of the song proved to be just right for the occasion: The ballad resonated with the hundreds of millions of people around the world who were saddened by Diana’s death.

Taupin has said that he was inspired to write the original song after hearing the phrase “candle in the wind” used in reference to Janis Joplin, who died in 1970 at age 27.

In a documentary on the making of Goodbye Yellow Brick Road, the classic album on which the ballad first appeared, Taupin said the song is about “the idea of fame or youth or somebody being cut short in the prime of their life. The song could have been about James Dean, it could have been about Montgomery Clift, it could have been about Jim Morrison… how we glamorize death, how we immortalize people.”

The manuscript of the song “Candle in the Wind” signed by Elton John and lyricist Bernie Taupin is displayed at the Althorp Estate outside London in 2001. (Photo: Sion Touhig/Getty Images)

It almost goes without saying that John never met Monroe. He was a 15-year-old kid when she died. But he was close friends with Diana. Only a month before Diana died, she and Elton had sat together at the funeral of their mutual friend, designer Gianni Versace.

In a BBC interview, Elton shed light on his friendship with Diana. He said he admired her commitment to fighting AIDS, something that many celebrities (and non-celebrities) in that era avoided like the plague. “It was considered to be a gay disease,” he said. “And for someone who was within the royal family — and who was a woman and who was straight — and to have someone care from the other side was an incredible gift. Also, she had this incredible ability… to make people feel at ease and make them feel that everything’s going to be all right. I haven’t experienced many people in my life who have had that ability. But she could walk into a room of people and make them feel as if everything is great.”

Princess Diana and pop star Elton John grieve for slain fashion designer Gianni Versace as Elton John weeps openly comforted by a friend at a memorial mass in Milan. Versace was shot dead in front of his Miami Beach mansion early last week. (Photo: Reuters)

In rewriting the “Candle” lyric, Taupin intended to make the song speak for all of England. “I thought it was very important to project it from a nation’s standpoint,” Taupin said. “I wanted to make it sound like a country singing it.”

Thus, he changed the opening lyric from “Goodbye Norma Jeane, though I never knew you at all…” to “Goodbye England’s rose, may you ever grow in our hearts…”

Remarkably, the original “Candle in the Wind” wasn’t released as a single in the U.S. back in the ’70s. The first two singles from Goodbye Yellow Brick Road were “Saturday Night’s Alright for Fighting” and the title track. “Candle in the Wind” was in line to be released as the third single, but, in a bold move, Elton instead released the R&B-edged “Bennie and the Jets,” which was far more of a departure from the sound of his past singles. (In that era, few albums spawned more than two or three singles.) Elton finally released “Candle in the Wind” as a single in 1987 as a track from his live album Live in Australia. The single went top 10 and received a Grammy nomination for Best Pop Vocal Performance, Male.

The Diana-inspired 1997 version of “Candle in the Wind” was released as a single on Sept. 13, 1997. It entered Billboard‘s Hot 100 at No. 1 and stayed on top for 14 consecutive weeks. It’s one of just three singles in chart history to spend its first 14 weeks at No. 1. (The other is “One Sweet Day” by Mariah Carey and Boyz II Men, which spent its first 16 weeks at No. 1 in 1995-96, and Luis Fonsi and Daddy Yankee’s “Despacito,” which tied “One Sweet Day’s” record just this week.)

“Candle ’97” was the first single to receive Diamond certification from the Recording Industry Association of America. The RIAA has certified the single for U.S. sales of 11 million copies. Guinness World Records declared “Candle in the Wind 1997” to be “the biggest-selling single since records began.” The book estimates the single’s global sales at 33 million. (Bing Crosby’s 1942 single “White Christmas” is believed to have sold even more — perhaps 50 million — but record-keeping wasn’t nearly as precise in that era.)

“Candle in the Wind 1997” sold 8,111,000 copies in the U.S. in 1997, according to Nielsen. That was slightly more copies than the year’s next three top-sellers combined. They were Puff Daddy & Faith Evans’ “I’ll Be Missing You” (featuring 112), Puff Daddy’s “Can’t Nobody Hold Me Down” (featuring Mase), and LeAnn Rimes’s “How Do I Live.” (The single’s B-side, “Something about the Way You Look Tonight,” received more airplay in the U.S. than “Candle” in all but the first three weeks of its chart run. But it was “Candle” that drove the single’s historic sales.) The song also entered the Official U.K. Singles Chart at No. 1. The song has sold nearly 5 million copies in the U.K. It has been certified the bestselling single of all time in the U.K. It took that title from Band Aid’s all-star 1984 release “Do They Know It’s Christmas?”

The song brought Elton a Grammy for Best Male Pop Vocal Performance, his second win in that category; he first won three years earlier for “Can You Feel the Love Tonight.” “Candle in the Wind 1997” was nominated for Best British Single at the 1998 Brit Awards, but lost to All Saints’ “Never Ever.” Elton did, however, receive a special award at the Brits that year, the Freddie Mercury Award.

Why did this single do so well? First of all, it’s a great song, well sung and well produced (by the late Sir George Martin, legendary producer of the Beatles). And many people around the world wanted to scoop up a keepsake connected to the late princess. Also, many wanted to support the Diana, Princess of Wales Memorial Fund, which received all artist and composer royalties and record company profits from the sale of the single.

Some of Elton’s greatest honors have come since the release of the single. He was knighted by Queen Elizabeth II on Feb. 24, 1998. He received a Grammy Legend Award in February 2000. He received a Kennedy Center Honor in December 2004. In 2013, he received the first Brits Icon award in recognition of his lasting impact on U.K. culture.

John was 50 at the time of the release of “Candle in the Wind 1997.” He remains the oldest artist ever to enter the Hot 100 at No. 1. Since “Candle in the Wind 1997,” he has had only one other top 40 hit in the U.S.: “Written in the Stars,” a 1999 collaboration with LeAnn Rimes. The song was drawn from Elton and Tim Rice’s musical Aida, which ran on Broadway from 2000 to 2004.

Elton hasn’t performed “Candle in the Wind 1997” since Diana’s funeral service — not even at the all-star Concert for Diana, a benefit concert at Wembley Stadium on July 1, 2007. He continues to sing the original version of the song in his concerts, but not the revised version. He doesn’t want anyone to think he’s exploiting it. He wants to keep it singular and special — like the song’s subject.