Rick Davies, a founding member and principal songwriter of the British rock band Supertramp, died on Sept. 5 at his home on Long Island after a long illness. He was 81, the band said, offering condolences to his widow, Sue Davies.

"The Supertramp Partnership is very sad to announce the death of the Supertramp founder, Rick Davies after a long illness," the group's public statement said. "Rick passed away at his home on Long Island on September 5th. We had the privilege of knowing him, and playing with him for over fifty years. We offer our sincere condolences to Sue Davies."

Davies co-founded Supertramp in January 1970 with Roger Hodgson after the two met in 1969 in response to an advertisement seeking musicians. The band—later rounded out by Dougie Thomson, Bob C. Siebenberg and John Helliwell—rose to international prominence in the 1970s with a string of hits that included "Give a Little Bit," "The Logical Song," "Take the Long Way Home" and the multi-platinum album "Breakfast in America." The group earned several Grammy nominations during its peak years.

Born in Swindon, England, in 1944, Davies began his musical career as a drummer before moving to keyboards and songwriting. One of his early bands, Rick's Blues, included singer Gilbert O'Sullivan; O'Sullivan later described Davies as a mentor, according to Variety.

Supertramp's most commercially successful era came after the lineup solidified in the early 1970s. The partnership between Davies and Hodgson produced much of the band's best-known material, but creative differences grew over time. Hodgson left the group after the 1982 album "...Famous Last Words..." to pursue a solo career. Davies and the remaining members continued to record and perform, with the ensemble reuniting occasionally over subsequent decades.

The band's final studio album, "Slow Motion," was released in 2002. In 2015, Supertramp announced a 25-date European tour, but the run was cancelled after Davies was diagnosed with multiple myeloma that year and faced ongoing health challenges.

Davies's role in Supertramp spanned songwriting, keyboards and lead vocals on numerous tracks, helping to shape the band's melodic, piano-driven sound that combined pop hooks with progressive-rock tendencies. The group's albums sold millions of copies worldwide and secured a lasting place in 1970s rock playlists.

Tributes began to appear from fans and fellow musicians following the announcement. The band asked for privacy for Davies's family and specifically extended its condolences to his widow.

Details on funeral arrangements were not immediately released.