Patrick J. Geary is an American medieval historian and Professor of Western Medieval History at the Institute for Advanced Study in Princeton, New Jersey
Yes it's true, this is a dry and dull book if you don't understand the context of the documents it contains, but if you do, then it's incredibly cool. Read this to understand medieval laws and oaths, among other important ideas which characterized the time.
I would advise against casual reading for those who dabble in history, but I would recommend this highly for any serious history student, one who is either enrolled in college or has access to someone that is highly knowledgeable about the medieval period.
This is a good collection of primary source readings. There is nothing ground breaking in the readings, but they are a good starting point for anybody who is trying to get a better understanding of this fascinating period of history.