Karl Wallinger, songwriter, 66

Karl Wallinger, a Welsh songwriter and musician who played with the folk rock group the Waterboys and founded World Party, a one-man act that grew into an influential band, died March 10. He was 66.

His publicist announced the death but did not say where or how he died. Mr. Wallinger had a brain aneurysm in 2001 that forced him to stop performing for several years, during which he relearned how to speak and play instruments.

Mr. Wallinger had worked as musical director for a production of “The Rocky Horror Show” in London’s West End when he was recruited to the Waterboys as a keyboardist in 1983, contributing backing vocals and synthesizer to the band’s most commercially successful song, “The Whole of the Moon.”

The group’s founder, singer and guitarist Mike Scott, called him “one of the finest musicians I’ve ever known” in a post Monday on X.

Creative differences with Scott led Mr. Wallinger to go his own way in 1985 to start World Party, where he created a sound infused with influences of the Beatles, Bob Dylan, Van Morrison and Sly Stone.

Mr. Wallinger worked on Sinéad O’Connor’s debut album, “The Lion and the Cobra,” (1987); O’Connor, in turn, lent her vocals to his second studio album, “Goodbye Jumbo” (1990), which brought World Party a Grammy nomination for best alternative music performance. Mr. Wallinger was also one of many artists who collaborated with Peter Gabriel on the album “Big Blue Ball” (2008).

Karl Edmond De Vere Wallinger was born in Prestatyn, Wales, on Oct. 19, 1957. As a teen he played in a punk band with Nigel Twist and Dave Sharp, who would go on to form the rock group the Alarm.

Survivors include his wife, Suzie Zamit; two children, Louis Wallinger and Nancy Zamit; and two grandchildren.