John Albert Walker (b. 1938, Grimsby, Lincolnshire) was trained as a painter in a University art department in Newcastle upon Tyne from 1956 to 1961. In 1958, he won first prize in a painting competition organised by Tyne Tees Television (the judge was Lawrence Gowing).
On graduation he moved to London and worked in the Civil Service, public and art libraries, and for many years wrote art criticism for a range of art magazines and taught art history in a number of British art schools. Before he retired in 1999, he was Reader in Art and Design History at Middlesex University. He has written 15 books and over 100 periodical articles about Van Gogh, John Latham, Charles Saatchi, the fine arts and mass media, and visual representations of firefighters. In 2005 he resumed painting after a gap of two decades.