Cerebus was an anthropomorphic aardvark, living in a barbaric human world; the storyline began as a parody of Marvel's Conan comic stories, particularly those done by Roy Thomas and Barry Windsor-Smith. Over time the strip would develop and become more serious in tone; for its first few years it parodied various comics and characters (including Red Sonja and Michael Moorcock's Elric), but as time went on it became more and more a literary exercise. Sim's personal political beliefs became intertwined with the book's narrative so much that toward the end of its existence the book was a subject of controversy within the comic community.
Whether a masterpiece or a monument to self-indulgence, Cerebus stands as a testament not only to its creator's commitment to his work, but also as a success story completely removed from the major publishers within the industry such as Marvel or Image.
Early on, Sim had announced that he would publish the book for exactly 300 issues, and he lived up to his promise. The character of Cerebus died in the final issue.
Cerebus storylines are available in a series of graphic novels published and distributed by Sim's own Aardvark-Vanaheim Press.
In addition, the comic sometimes served as a showcase for the work of other struggling, independent comic writer/artists such as Mark Oakley, creator of Thieves & Kings.