Peter Koelewijn was born on 29 December 1940, the son of a fishmonger in the southern Dutch city of Eindhoven. At the age of thirteen, he received his first guitar. In 1957, he started writing his first songs in English. He started his first band at secondary school with guitarists Karel Jansen and Roelof Egmond and singer Anneke Grönloh. Later on, Harry van Hoof (who later became a famous conductor), and drummer Peter van der Voort, joined the band. Around the same time, Grönloh left the band. Koelewijn has two children, Kim and Joep, who share his musical talent.