Fantasy films were the focus of Famous Monsters of Filmland and Monster World, edited by Forrest J. Ackerman. Warren soon published Spacemen (magazine) magazine and in 1960 Help! magazine with the first employee of the magazine being Gloria Steinem. After first introducing what he called "Monster Comics" in Monster World, Warren expanded in 1964 with horror-comics stories in what would become a highly popular duo of magazines, Creepy and Eerie. As discussed by Warren in the book 'The Warren Companion', the format needed to be magazines to get around the restrictions of the Comics Code Authority
The Comics Code saved the industry from turmoil, but at the same time, it had a cleansing kind of effect on comics, making them 'clean, proper and family-oriented'. How do I surmount this? Fasten your seatbelts. We would overcome this by saying to the Code Authority, the industry, the printers, and the distributors: 'We are not a comic book; we are a magazine. Creepy is magazine-sized and will be sold on magazine racks, not comic book racks'. Creepy's manifesto was brief and direct: First, it was to be a magazine format, 8 1/2" x 11", going to an older audience not subject to the Code Authority.
By publishing graphic stories in a magazine format to which the Code did not apply, Warren paved the way for such later graphic-story magazines as the American version of Heavy Metal; Marvel Comics' Epic Illustrated; Psycho and other "horror-mood" series from Skywald Publications; and Warren's own line of magazines.
Russ Jones was the founding editor of Creepy in 1964. A year later, Archie Goodwin succeeded him, with Joe Orlando acting as a behind-the-scenes story editor. Goodwin, who would become one of comics' foremost and most influential writers, helped to establish the company as a major force in its field. From 1965 to 1966, Warren also published the four-issue Blazing Combat, a war-comics magazine with anti-war themes.
During the next two-and-a-half years, Warren's publications consisted primarily of reprints from the early issues. During this period, a variety of editors ran the magazines including Bill Parente, Nicola Cuti, and Warren himself. Things started picking up again for Warren in 1969 with the premiere of its third horror magazine, Vampirella. Many of Warren's original artists returned during this period, as would Goodwin for a period of time in 1970 and 1971. After Goodwin's second departure, editors would J.R. Cochran. The art director was Billy Graham.
In 1971, Warren began using artists from the Barcelona studio of Spanish agency Seleccionnes Illustrada. Over the next few years, Spanish artists would dominate the magazines. Additional Spanish artists from S.I.'s Valencia studio began freelancing for Warren in 1974.
In 1973, new editor Bill DuBay, who had originally joined the company as an artist early in 1970, transformed Warren's magazines to create a uniform style. The following year, Warren Publishing was dissolved and replaced by Warren Communications, a sister company James Warren had founded in 1972. Dubay was editor for all three of Warren's horror magazines until 1976, except for a short period of time in 1974 where Goodwin returned to edit four issues of Creepy and two of Vampirella. During this time the frequency of Warren's magazines was upped to nine issues a year.
After Dubay's departure, Louise Jones, his former assistant, headed the editorial staff from 1976 to 1980. Toward the end of Dubay's period of editorship many American artists had returned to the magazines, including John Severin, Alex Toth, and Russ Heath and they contributed many stories during Jones' time as editor. Former DC Comics publisher Carmine Infantino would also join the company during this period and pencil over 50 stories. Much like the wave of Spanish artists that dominated throughout the mid-1970s, a number of artists from the Philippines would begin contributing during this period. Dubay returned as editor after Jones' departure, using the alias "Will Richardson".
Towards the end of the 1970s, Warren started publishing two new magazines edited by Dubay: the science-fiction anthology 1984, in 1978 (it would change its name to 1994 two years later); and, in 1979, The Rook, starring a time-traveling adventurer whose stories had appeared in Eerie since 1977.
Illustrators included such established artists as Orlando, Neal Adams, Gene Colan, Frank Frazetta, Angelo Torres, Roy G. Krenkel, Gray Morrow, Al Williamson, Johnny Craig, Reed Crandall, Alex Toth, John Severin, Russ Heath and Wally Wood, plus a newer group of talents, including Dan Adkins, Richard Bassford, Roger Brand, Frank Brunner, Rich Buckler, Dave Cockrum, Nicola Cuti, Richard Corben, Al Hewetson, Ken Kelly, Mike Royer,Tom Sutton and Berni Wrightson.
The Spanish artists from Selecciones Ilustradas included Esteban Maroto, José Ortiz, Luis Bermejo, Rafael Aura Leon, Luis Garcia, Jose Gonzalez, Isidro Mones, Martin Salvador, Fernando Fernandez, Leopold Sanchez, Ramon Torrents, Jose Bea, Vicente Alcazar, Jose Gual, Felix Mas and Jaime Brocal. Artists from the Philippines included Alex Niño, Rudy Nebres, Alfredo Alcala and Abel Laxamana. Other international artists who worked for Warren include Gonzalo Mayo (Peru), Pablo Marcos (Peru), Leo Duranona (Argentina) and Paul Neary (U.K.).
Cover artists for Creepy, Eerie and Vampirella included Adkins, Frazetta, Kelly, Morrow, Sutton, Ken Barr, Vaughn Bodé, Pat Boyette, Ron Cobb, Richard Conway, Jack Davis, H.R. Giger, Basil Gogos, Bill Hughes, Terrance Lindall, Gutenberg Monteiro, Albert Nuetzell, Vic Prezo, Manuel Sanjulian, Vincente Segrelles, Kenneth Smith, Enrich Torres and Boris Vallejo.