The extraordinarily diverse output of composer Karl Jenkins has encompassed genres as numerous as jazz, rock, film music, advertising music, New Age music, and classical composition, largely choral. He is perhaps best known for the song Adiemus, for a series of classical or New Age works derived from it, and for the widely performed mass setting The Armed Man.

Jenkins was born in Penclawdd, Swansea, Wales, on February 17, 1944. His father was a local schoolteacher, organist, and choir director who gave him his first music lessons. Jenkins attended Cardiff University, studying music, and went on for further work at the Royal Academy of Music. He later earned a doctorate in music from the University of Wales. In the late 1960s, Jenkins became interested in London's vigorous jazz scene, playing saxophones, keyboards, and, more unusually, oboe. He performed with a band led by bassist Graham Collier and founded the jazz fusion band Nucleus, which performed at the Montreux Jazz Festival in 1970. In 1972, Jenkins joined the progressive rock band Soft Machine, composing many of the songs on their successful albums of the 1970s and early 1980s.

In the 1980s and 1990s, Jenkins enjoyed a successful career as a composer of music for advertising, winning two industry awards. Some of his advertising music later found its way into his classical compositions. The most significant example of this was his song Adiemus, which was sung by Miriam Stockley and first appeared in 1994 in a Delta Airlines ad. The song was a hit in its own right, and the material (later simply the concept) continued its life through five extraordinarily successful Adiemus albums (Songs of Sanctuary, Cantata Mundi, Dances of Time, The Eternal Knot, and Vocalise). These albums have been categorized as New Age or classical; they incorporate various influences from Celtic music, world music, electronic music, and more, into a basic theme. Just as successful has been The Armed Man (1999), a setting of the Catholic mass incorporating the medieval song The Armed Man (L'homme armé) along with other texts and musical materials. The mass has been performed by hundreds of choirs, many of them nonprofessional, in Britain and beyond. The Armed Man featured a 70-piece orchestra, and in the 21st century, Jenkins has focused on yet larger classical works. The giant choral work The Peacemakers (2014), with texts from Martin Luther King, Jr., the Dalai Lama, Nelson Mandela, Gandhi, Mother Teresa, and Anne Frank, included a 1,000-voice choir called The Really Big Chorus on its 2012 debut recording. Jenkins' 2016 work Cantata Memoria: For the Children commemorated the victims of the Aberfan Disaster, a mine waste collapse in Wales that killed 116 children.

Jenkins has remained active into his 70s and continues to issue albums, mostly under his name. In 2019, the album Miserere: Songs of Mercy and Redemption appeared on the Decca label; that year also saw the release of Karl Jenkins: Piano, featuring the composer's performances of his relatively underexposed piano music. ~ James Manheim, Rovi