- “My idea was, which I used in advertising in subsequent years, was this idea of small books for small hands. The idea of four stories in one little book was a very good idea, in my view, as bedtime stories because parents, in fact, don't like to go through 64 pages; they would much prefer to go through 16 pages and stop.”
- ―Eric Marriott on the format of the Railway Series, The Thomas the Tank Engine Man documentary
Eric Marriott trained in the editorial and print departments of the Cambridge University Press before doing six years of service in the British Army during the Second World War. With the return of peace in 1945, Marriott rejoined the C.U.P. in order to expand his knowledge of the administrative side of publishing. His ambition, however, was to work for a more commercial publisher, "away from the cloistered atmosphere of the University Press".
Answering an advertisement in the Times Literary Supplement, Marriott went to Leicester to meet Franklyn Edmund Ward. At the start of the interview, Ward asked Marriott for the full details of his birth so that he could consult with an astrologer. Whether due to Marriott's previous experience or because it was written in the stars, Ward offered him the job of editor and Marriott joined Edmund Ward Ltd. in January 1947. Edmund Ward was a relatively small-scale operation, publishing only a handful of titles per year and lacking the sophisticated equipment used by other companies, with books still being sewn by hand. Because of this, whilst his formal title may have been "Editor", he was also expected to handle rights and publicity, as well as oversee the printing and marketing of the titles on Edmund Ward's list.
Two of the titles on that list were The Three Railway Engines and Thomas the Tank Engine by the Rev. W. Awdry, which Ward had shown Marriott at his interview. Marriott could see a future for the "humanised engines" and due to his young daughter he found the idea of a series of "small books for small hands" very attractive. His new employer did not share Marriott's enthusiasm for the books and was content with simply reprinting the two titles he already had. Marriott was adamant that they should peruse a series alongside reprinting the books, believing that while Ward's policy of continuously reprinting existing books instead of publishing new ones was sound thinking in the immediate aftermath of the war, it was not good for the future, when publishing houses would have to compete more regularly with new titles. Marriott was able to convince Ward to peruse a series and the Rev. W. Awdry was commissioned to write James the Red Engine in 1948.
Eric Marriott assisted Brian Sibley with writing his biography of the Rev. W. Awdry by allowing Sibley access to "invaluable" archives and reviewing parts of the typescript. He was interviewed with Peter Edwards in The Thomas the Tank Engine Man documentary, at which time he was living near Maldon, Essex and died shortly afterwards.
- James the Red Engine (1948)
- Tank Engine Thomas Again (1949)
- Troublesome Engines (1950)
- Henry the Green Engine (1951)
- Toby the Tram Engine (1952)
- Gordon the Big Engine (1953)
- Edward the Blue Engine (1954)
- Four Little Engines (1955)
- Percy the Small Engine (1956)
- Eight Famous Engines (1957)
- Duck and the Diesel Engine (1958)
- The Little Old Engine (1959)
- The Twin Engines (1960)
- Branch Line Engines (1961)
- Gallant Old Engine (1962)
- Stepney the "Bluebell" Engine (1963)
- Mountain Engines (1964)
- Very Old Engines (1965)
- Main Line Engines (1966)
- Small Railway Engines (1967)
- Enterprising Engines (1968)
- Oliver the Western Engine(1969)
- Duke the Lost Engine (1970)
- Tramway Engines (1972)
- Painting Books (1950)
- Pre-Cut Model Engine Books (1957)
- Railway Map of the Island of Sodor (1958/1971)
- The Railway Series: Surprise Packet (1972)
- Eric Marriott's name appears on a building at Tidmouth Harbour in the second illustration of Duck Takes Charge in Percy the Small Engine.
- Diesel's appearance in 1958 was a request by Marriott, “In order to keep the series up to date”, as more diesels were being seen on British Railways.
- Peter Edwards' portrait of Gordon was modelled on Marriott's “splendid nose”.