In 1980 Italian medievalist, semiotician, philosopher, literary critic and novelist Umberto Eco published Il nome della rosa. The English translation by William Weaver appeared in 1983 under the tile of The Name of the Rose. It is an intellectual murder mystery, combining semiotics, biblical analysis, medieval studies and literary theory, set in an Italian monastery patterned after the abbey and library at Bobbio, Italy, in 1327. Just a few of the appealing aspects of the plot, without a "spoiler," include an unknown treatise by Aristotle, On Laughter, a mysterious labyrinthine library, a medieval monk detective patterned after Sherlock Holmes, narration by a "sidekick" patterned after Dr. Watson, and many other features of interest to readers of this database. The title of the novel alludes to the literary tradition of Le Roman de la Rose.
This novel clearly attracted numerous contributors to the Wikipedia, and their articles both on Eco and The Name of the Rose provide such detailed and insightful analysis that it would be pointless to summarize. Instead I recommend that you follow the links for further information, and read the book if it suits your taste.
In 1983 Eco published an informative small illustrated book explaining aspects of the novel entitled Positille a Il nome della rosa. This was also translated into English by William Weaver as Postscript to the Name of the Rose, and published in 1984. I found reading Eco's Postscript very worthwhile.