This is a very serious study of the primary method of Social and political organization for Western Europe from about 950 to 1250 CE. It is very detailed about the exact gradations between Homage, vassalage, and having a liege lord relationship. If your eyes haven't glazed over yet, this is the book for you. Bloch tries to define why the simple idea that "I have the ownership of the land and I desire you to do a service for me. The only way I can pay you is to grant you and your servants the right of use a certain amount of that land in return." was open to a wide range of abuses, and, even at the time, misapprehensions.
He shows that the simple post-Norman conquest English system was wonderfully simple when compared with the same idea anywhere else in Europe. If you want to study the matter in more detail there's an extensive bibliography.
After reading this book, you will never look at simple Medieval based fantasy social structure again without a wry smile.
This book was published in French in 1939, and translated into English in 1961. ( )