He does talk about Church politics of the Middle Ages, but it's to frame the larger questions that he raises about spirituality, the value of books, the nature of learning and ignorance and the way politics manipulates EVERYTHING - learning, God, even laughter.

I'll admit that Foucault's Pendulum does require a lot of esoteric knowledge. Of course, I was obsessed with the occult in middle school, so I didn't pick up on a "I know so much" vibe from Eco. My business partner (Gary) tried to read Foucault's Pendulum but hadn't strayed as deeply into occultism and so he gave up because for him there were too many references that led to having to read half of the pages on wikipedia.