I read the book when it first came out and became a lifelong Umberto Eco fan. I saw the movie version and remember it as good, not great. This TV version, headlined by John Turturro, sticks closer to the book.
It’s an 8-part series, and the first 3 episodes are heavy going. The series dramatizes all the backstories in the book, many of which are told in flashback, which can make the timeline very confusing. Around episode 4, however, the story lines start to intersect, and the last few episodes are very good.
The English Franciscan friar William of Baskerville, known for his power of logical reasoning, and his faithful assistant Adso, are of course fictional, as is the abbey with its mysterious library. But Bernard Gui, the Grand Inquisitor, was a real person. And there was a great debate between the Dominicans and the Franciscans on the subject of clerical poverty, although it was held at the Papal palace in Avignon and not, as in this story, in a remote Italian abbey. Gui argued for the Dominicans; the Franciscans were represented by William of Ockham, an English Franciscan famous for his Razor.