The first issue of Other Worlds
s stable-mate at Clark Publishing
American science fiction magazines first appeared in the 1920s with the appearance of Amazing Stories, a pulp magazine published by Hugo Gernsback. The beginnings of science fiction as a separately marketed genre can be traced to this time, and by the end of the 1930s the field was undergoing its first boom, but World War II and its attendant paper shortages led to the demise of several titles. By the late 1940s the market began to recover again. From a low of eight active magazines in 1946, the field expanded to 20 in 1950, and a further 22 had commenced publication by 1954. Imagination was launched in the middle of this publishing boom.
The groundwork was laid in 1947, when Clark Publishing, the company that would publish the first issue of Imagination, was incorporated in Evanston, Illinois, by Raymond Palmer. He worked for Ziff-Davis as the editor of Amazing Stories and did not leave until the end of 1949, but he launched two magazines under the Clark name before that date: Fate, in the spring of 1948, and Other Worlds, the first issue of which was dated November 1949. Both of these magazines listed their editor as "Robert N. Webster", a pseudonym Palmer adopted while he was still at Ziff-Davis because of the conflict of interest. The second issue of Other Worlds reported that Webster and Palmer were going to edit together; by the third issue, dated March 1950, the pretense had been dropped and although there was no masthead listing the editor, the editorial was simply signed "Rap" (for "Raymond A. Palmer"). At the 1949 World Science Fiction Convention in Cincinnati, held over the weekend of 3–5 September, Palmer announced that he had left Ziff-Davis and described his plans for Clark Publishing. He also met and hired Bea Mahaffey, a 21-year-old science fiction fan attending her first convention, as his assistant editor.
With Fate and Other Worlds launched, Palmer began to plan for a new magazine, to be called Imagination. Material for the first two issues had been assembled by mid-1950, but in the early summer Palmer fell down his basement stairs and was left paralyzed from the waist down. While he was hospitalized, much of the work of editing both Other Worlds and Imagination was done by Mahaffey, who coped well, despite her inexperience. An assistant, Marge Budwig Saunder, was hired to read the slush pile and help out. The magazine's first issue, dated October 1950 on a planned bi-monthly schedule, appeared on news stands 1 August 1950. However, in September that year, Ziff-Davis made the decision to move to New York from Chicago; Palmer promptly contacted William Hamling, who did not want to relocate and suggested that Hamling take over Imagination. Like Palmer, Hamling had made preparations to leave Ziff-Davis by establishing a separate publishing company, Greenleaf Publishing, and in November 1950 Hamling left Ziff-Davis and became Imagination's editor and publisher.
In 1954 Hamling started a companion magazine, Imaginative Tales; in addition, his company Greenleaf Publishing was the publisher of Rogue, a men's magazine modelled after Playboy. In 1957 the liquidation of American News Company, a major distributor, meant that many magazines had to scramble to find new distributors. Independent distributors often required that the magazines be monthly, and that they be in a larger format than the digest-size common in science fiction magazines. The larger format required higher revenue to be profitable, but in many cases it proved impossible to attract the additional advertising income that would have kept the magazines afloat. By the end of 1958, many titles had disappeared as a result, with Imagination one of the victims; Hamling closed down both Imagination and its sister magazine to invest the money in Rogue instead. The last issue of Imagination was October 1958, the 63rd issue, while Imaginative Tales, retitled Space Travel, ceased with the November 1958 issue. There was no indication in either magazine that the end had come, though the last issue of Imagination omitted its letter, book review and pen-pal columns, all of which had appeared regularly in prior issues.
Circulation figures were not required to be published annually until the 1960s, so the actual circulation figures are not known. For comparison, the more successful Magazine of Fantasy and Science Fiction, which had been launched the previous year, is known to have had a circulation of just under 60,000 copies for its first issue, dated Fall 1949.