Ashen Knight - The Bloody Order
Ashen Knights covers the world of knights. It does a good job of giving us the setting as it really was (or at least as it should have been)¸ and how it would be in a world with the undead lurking around. They do note that the Road of Chivalry presented in the main rules doesn't quite jibe with the way Knighthood and chivalry were¸ and present an alternate Via Equitum. The book covers the life of a knight¸ including some interesting stuff on various knightly orders (including the oh so doomed & stylish Templars) and a breakdown of the knightly virtues. There's also info on how to run knights who are vampires.
old Steel¸ Hot Blood
The clash of arms on the battlefield as two knights meet in combat. The thunder of horses hooves as lances are couched for impact. The oaths sworn to king¸ God and liege lord. The sons of Caine are no strangers to these things. Now you too can discover what they have known in their blood for centuries.
Even Caines Childer Know Honor