Saint Louis:  Louis IX, Most Christian King of France - Margaret Wade Labarge Though 40 years old, Margaret Labarge's book lays out the basic course and essential importance of Saint Louis' reign (1226-1270) in clear, straightforward prose. France was blessed (or cursed depending upon where your sympathies lie) by a century's worth of reasonably capable kings and ministers who created the nation of "France," starting with Louis' grandfather Philip Augustus (1180-1223). (Of course, it helped that the Angevin realm imploded upon Henry II's death.)

It's also a very sympathetic portrait of the king. While Louis definitely had a sense of noblesse oblige and worked diligently to ensure equity and justice within his realm (within the constraints of Medieval sensibilities - he was not a proto-democrat or man of the people), Labarge glosses over the less savory aspects of his religious conviction like his anti-Semitism or the suppression of heresy. And, for that matter, the appalling waste and uselessness of his two crusades.

If I were to classify this book I would say that it's a good narrative of the king's reign for an undergraduate who's doing serious studies in Medieval history. It's not detailed enough for a post-grad yet it's far too specialized for the simply curious. There's a reasonably helpful family tree and parallel chronologies so readers can orient themselves but I believe "dramatis personae" would have be helpful in books like this. Just a list of the "characters" and brief biographies as the names fly fast and furious; it's easy to be overwhelmed. In my case, post-grad days in UCLA's Medieval history department served me well but anyone without some familiarity with the period will be lost.

Just an observation, but it's remarkable how much we can know about Medieval people (and not just the nobility). It's no where near the information that modern historians have access to but we can be glad that our ancestors (at least the Europeans amongst us) were so anal about keeping records. In that vein, I want to mention the site Medieval Soldier - http://www.icmacentre.ac.uk/soldier/database/ . I heard about this site on an NPR program (I think it was "The World"). It's digitized the records of the English army from the period around Henry V's reign (c. 1400). To randomly wander the site is a pleasure and an education.