Sir Peter Siddell was born in Auckland in 1935 and educated at Mt Albert Grammar School and the Auckland College of Education. In 1960 he married artist Sylvia Siddell. Siddell has painted full-time since 1972 when he held his first solo show. He has since taken part in many exhibitions in both public and commercial galleries. Siddell's realist paintings are identified mainly with depictions of the environs of Auckland. While his works appear to be records of actual places, his paintings have a subjective component, and might be better described as magic realism than truly realistic. The cityscapes and townscapes in Siddell's paintings are rendered empty, but with the unnerving suggestion of events occurring outside the picture area. In this sense, his work can be compared to the metaphysical works of Giorgio de Chirico.

Siddell's work is held in the permanent collections of all New Zealand major public art galleries, as well as many private, corporate and institutional collections. He received a QSO in the 1990 New year's honours list, and a DCNZM in 2008.

In February 2011, a comprehensive survey of his art career was published by Random House New Zealand, "The Art of Peter Siddell." Siddell is the second New Zealand artist to be knighted: the first was Sir Toss Woollaston