Keith Reid, the primary lyricist for Procol Harum, has died at the age of 76.

The songwriter’s passing was confirmed by the band, who posted a tribute to Reid on their Facebook page.

“We are sad to hear of the death of Keith Reid,” the message began. “An unparalleled lyricist, Keith wrote the words to virtually all Procol Harum songs, as well as co-writing the John Farnham hit ‘You’re the Voice.’ His lyrics were one of a kind and helped to shape the music created by the band. His imaginative, surreal and multi-layered words were a joy to Procol fans and their complexity by design was a powerful addition [to] the Procol Harum catalog. Our thoughts go out to his family and friends.”

Born in Hertfordshire, England in 1946, Reid left school at an early age to pursue a career in songwriting. He met singer Gary Brooker in 1966, who at that point had departed his previous group, the Paramounts. Reid and Brooker quickly developed a kinship and began writing together. Initially the material was meant for other artists, but when the two couldn’t find enough interest in their work, they opted to create a band of their own.

Brooker would be front and center as Procol Harum’s vocalist, while Reid remained the band’s primary lyricist. Though the group went through a wide range of lineup changes, with many musicians coming and going, Brooker and Reid remained steady forces in Procol Harum during the band’s initial run from 1967 to 1977.

During that time frame, the band released nine studio albums. Their most successful single also happened to be their first. Released May 12, 1967, “A Whiter Shade of Pale” hit No. 1 in the U.K. and No. 5 in America. It sold more than 10 million copies during the Summer of Love, ranking it among the best-selling singles in history.

“It’s sort of a film, really, trying to conjure up mood and tell a story,” Reid noted to Songfacts in 2009, explaining the track’s lyrics. “It’s about a relationship. There’s characters and there’s a location, and there’s a journey. You get the sound of the room and the feel of the room and the smell of the room. But certainly there’s a journey going on, it’s not a collection of lines just stuck together. It’s got a thread running through it.”

Listen to ‘A Whiter Shade of Pale’

While Procol Harum maintained a passionate fanbase, they never released a song that matched “A Whiter Shade of Pale”’s commercial success. Follow-up single “Homburg” hit No. 6 in the U.K. and No. 34 in America, while 1972’s “Conquistador” peaked at No. 22 and 16, respectively.

When Procol Harum broke up in 1977, Reid began writing for other artists. In the mid-‘80s, he founded a management company in New York, before later reuniting with Brooker and Procol Harum in 1991. He contributed to two further albums with the group, The Prodigal Stranger (1991) and The Well’s on Fire (2003). Procol Harum’s final album, Novum, was released in 2017, but Reid did not contribute to the LP.