Elis Pehkonenwas born in Swaffham, Norfolk, England in 1942. He was a pupil at Hamond's Grammar School, Swaffham, where he was taught Art by Harry Carter, the man who created many Norfolk Village signs and nephew of Howard Carter (the Egyptologist who discovered the tomb of Tutankhamen).

In 1960, Elis had his first composition lesson with Benjamin Britten. That same year he won a composition scholarship to the Royal College of Music, where he studied with Peter Racine Fricker until 1964. He also had consultation lessons with Lennox Berkeley, Alan Ridout, Geoffrey Bush, Richard Rodney Bennett, and Anthony Payne.

His first commission, at Britten's recommendation, was in 1966 for the Kings Lynn Festival, the Incidental Music for Everyman. His first work to be broadcast on Radio 3 was the Three Songs to poems by Laurie Lee, whom he met when he moved to Gloucestershire in 1964.

It was in Cirencester where Elis Pehkonen composed the first version of his major work Requiem, the first ever complete setting of the Missa Pro Defunctis, lasting 1 hour 50 minutes. From 1967 to 1979, Elis taught at Cirencester School, where he continued the tradition begun by Peter Maxwell Davies of involving pupils in performing contemporary music. For eight years Elis conducted the Cirencester School Percussion Ensemble in dozens of concerts and broadcasts, which included music by David Bedford, Brian Dennis, Philip Lane, James Patten, and many other notable composers.