Cardassian speculative fiction is a literary genre in the worlds of the Cardassian Theonomy that encompasses the genres known to Earth literature as science fiction and fantasy, as well as the religious-influenced versions of both genres. To the Cardassian follower of the Oralian Way, distinctions between these genres would seem artificial, and though there are different "flavors" of speculative fiction, with some leaning more towards hard science, some focusing more on the spiritual implications of futuristic or alternate-universe scenarios, and others focusing on a more magical approach, all of it falls under the same heading.
Some of this likely stems from the widely-held Oralian belief that there is no conflict between science and religion; therefore Cardassian authors tend to be quite comfortable addressing hard science concepts and their attendant ethical and theological issues in the same works.
This genre has been in existence in its current form for at least 700 years (prior to 500 years it is known as Hebitian speculative fiction) and possibly longer, evidenced by the books the young Skrain Dukat had read, some of which went back at least that far. (Sigils and Unions: Catacombs of Oralius--"The Desolate Vigil")
Main Star Trek: Sigils and Unions universe
In the main universe, where the Oralian Way was driven underground in the wake of the Cataclysm, and the Cardassian Union rose in its place, Hebitian speculative fiction was similarly driven underground, into exile, or so heavily monitored that the nature of the genre underwent fundamental change until only something like Earth science fiction (and even then, strongly censored and monitored by the state) was left.