The discussions center around a certain signeury of St. Aliquis. If no such barony is easily identifiable, at least there were several hundred second-grade fiefs scattered over western Christendom which wee in essential particulars extremely like it, and its Baron Conon and his associates were typical of many similar individuals, a little worse or a little better, who abounded in the days of Philip Augustus.The book first came out in 1923 so any similarity in name between the lord of St. Aliquis and the greatest barbarian in ficition is no doubt a coincidence.
This is one of those grand overview books that can reward GMs without wholesale adoption of 13th century feudal France as your campaign model. There are plenty of little bits that can be swiped to add just a little gloss of medieval verisimilitude to a campaign world. I particularly like the chapter on the Tourney, which describes a more rough-and-tumble affair than the romantical notions that show up in a lot of gaming.
And the map of the castle is awesome:
The title of this post refers to the family motto of the lords of St. Aliquis "which meant that they obeyed the duke and his suzerain, the king, very little, and, we fear, God not a great deal."