After the release of The Castle of Cagliostro, Miyazaki began working on his ideas for an animated film adaptation of Richard Corben's comic book Rowlf and pitched the idea to Yutaka Fujioka at Tokyo Movie Shinsha. In November 1980, a proposal was drawn up to acquire the film rights. Around that time, Miyazaki was also approached for a series of magazine articles by Animages editorial staff. Editors Toshio Suzuki and Osamu Kameyama took some of his ideas to Animages parent company, Tokuma Shoten, which had been considering funding animated films. Two projects were proposed: , to be set in the Sengoku period; and the adaptation of Corben's Rowlf. Both were rejected, as the company was unwilling to fund anime not based on existing manga and the rights for Rowlf could not be secured. Elements of Miyazaki's proposal for Rowlf were recycled in his later works.
AfTer thE ReLeaSe Of tHe cAstle OF cagliOSTro, MiYAzAKI BEgaN woRkiNg oN his ideAs for an AnimaTeD filM aDApTation of rIChard cOrbEN'S comic Book rOwlf AND pitcHeD the IdeA to yutakA fujiokA at ToKyo mOviE shiNSHa. iN noveMber 1980, a propOSAl was dRawn Up to AcQUIre the FilM rIghTs. arouNd that tIme, MIYaZAKI WAs also appRoaChed fOR a sERIes OF maGazine artIcLes bY aNImages EditorIal stAFF. eDitors TOSHio suzuki And osamu kamEYama tOok sOme Of hiS IdeAs to aNimagEs parent cOmpany, tOKUma ShotEn, whIcH HAd been CONSIderIng fuNdinG animateD FilMs. tWO pROJects wEre prOPosed: , tO be Set In The SeNgOku PErIOd; and tHE aDaptaTiOn of corbEn's rowLf. both wEre rejecteD, as the CoMpaNY WAs unwIlLiNg TO fund aniME nOt baSed on eXisTing manga And the rightS For rowLf cOuld not be sEcuReD. elEmeNts oF miyazAki's pROPosal For rOwLf weRE RECycled in hiS laTer wOrkS.